Patent Application
20250028295
The present invention relates to a bonding method, a bonding apparatus and an article manufacturing method.
Japanese Patent Laid-Open No. 2000-68296 proposes a technique of, in a bonding apparatus, improving the yield of an article (device or the like), which is manufactured by bonding the first object and the second object, by bonding non-defective objects together and bonding defective objects together when bonding the first object and the second object.
However, if there is an imbalance in the number of non-defective objects between the conveyance units of the first objects and the conveyance units of the second objects sequentially supplied to the bonding apparatus, the conventional technique sometimes needs to perform bonding not only in a combination of non-defective objects but also in a combination of a non-defective object and a defective object. In this manner, in the conventional technique, it is not always possible to obtain a sufficient effect of improving the yield.
The present invention provides a technique advantageous in improving the yield of a bonded object obtained by bonding the first object and the second object.
According to one aspect of the present invention, there is provided a bonding method of conveying a plurality of carriers and a plurality of substrates to a bonding apparatus and boding a first object and a second object, the plurality of carriers each holding a plurality of first objects, the plurality of substrates each having a plurality of second objects formed thereon, the method including obtaining rank information including data indicating ranks of the respective first objects for each of the plurality of carriers and data indicating ranks of the respective second objects for each of the plurality of substrates, deciding, based on the rank information, a conveyance order of the plurality of carriers and a conveyance order of the plurality of substrates, and conveying the plurality of carriers and the plurality of substrates to the bonding apparatus in accordance with the conveyance orders decided in the deciding, and bonding the first object and the second object.
Further aspects of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note, the following embodiments are not intended to limit the scope of the claimed invention. Multiple features are described in the embodiments, but limitation is not made to an invention that requires all such features, and multiple such features may be combined as appropriate. Furthermore, in the attached drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.
A description will be given below assuming that a carrier (first carrier) is a dicing frame holding (mounted with) a plurality of separated dies (first objects) on each of which a semiconductor device has been formed, and a substrate (second carrier) is a wafer on which a plurality of dies (second objects) each including a semiconductor device have been formed. However, the carrier and substrate are not limited to this.
The first object includes, in addition to the separated die, for example, a stack of some already separated dies, a small piece of a material, an optical element, a MEMS, a structure, or the like.
The second object includes, in addition to the die of the semiconductor device formed on the wafer, for example, a silicon interposer as a silicon wafer with wirings formed thereon, and a glass interposer as a glass wafer with wirings formed thereon. The second object also includes an organic interposer as an organic panel (PCB) with wirings formed thereon, a wafer formed with a semiconductor device, to which some dies including semiconductor devices have already been bonded, and the like.
The bonding method of the first object and the second object is also not limited. The bonding method of the first object and the second object includes, for example, bonding using an adhesive agent, temporary bonding using a temporary adhesive agent, bonding by hybrid bonding, atomic diffusion bonding, vacuum bonding, bump bonding, and the like. In this manner, the bonding method of the first object and the second object includes various temporary bonding methods and permanent bonding methods.
Industrial application examples of the bonding apparatus as one aspect of the present invention are, for example, application examples described below.
The first application example is manufacturing of a stacked memory. When the bonding apparatus as one aspect of the present invention is applied to manufacturing of a stacked memory, the first object is a separated memory die, and the second object is a memory die as a semiconductor device formed on a wafer. In manufacturing of a stacked memory, in general, about eight layers are stacked. Hence, in bonding of the eighth layer, the second object is a substrate as the wafer to which six layers of memory dies have already been bonded. Note that the final layer may be a driver die for driving the memories.
The second application example is heterogeneous integration of a processor. The mainstream of a conventional processor is an SoC obtained by forming a logic circuit and an SRAM in one semiconductor element. To the contrary, in heterogeneous integration, respective elements are manufactured on separate wafers while applying a process optimal for each element, and bonded to manufacture a processor. This can implement cost reduction and yield improvement of the processor. When the bonding apparatus as one aspect of the present invention is applied to heterogeneous integration, the first object is a die such as an SRAM, an antenna, or a driver separated after probing. The second object is a logic die as a semiconductor device formed on the wafer. Normally, different dies are sequentially bonded. Hence, the bonded objects on the second object sequentially increase. For example, in a case of starting bonding from an SRAM, when bonding the die next to the SRAM, the logic wafer with the SRAM bonded thereto serves as the second object.
The third application example is 2.5D bonding using a silicon interposer. The silicon interposer is a silicon wafer with wirings formed thereon. The 2.5D bonding is a method of bonding separated dies using the silicon interposer, thereby electrically bonding the dies. When the bonding apparatus as one aspect of the present invention is applied to die bonding to the silicon interposer, the first object is a separated die, and the second object is a silicon interposer as a silicon wafer with wirings formed thereon. In general, a plurality of types of dies are bonded to the silicon interposer. Hence, the second object also includes a silicon interposer with several dies bonded thereto.
The fourth application example is 2.1D bonding using an organic interposer or a glass interposer. The organic interposer is an organic panel (PCB substrate or CCL substrate) used as a package substrate, on which wirings are formed. The glass interposer is a glass panel with wirings formed thereon. The 2.1D bonding is a method of bonding separated dies to the organic interposer or the glass interposer, thereby electrically bonding the dies by the wirings on the interposer. When the bonding apparatus as one aspect of the present invention is applied to die bonding to the organic interposer, the first object is a separated die, and the second object is an organic panel formed with wirings. When the bonding apparatus as one aspect of the present invention is applied to die bonding to the glass interposer, the first object is a separated die, and the second object is a glass panel formed with wirings. In general, a plurality of types of dies are bonded to the organic interposer or the glass interposer. Hence, the second object also includes an organic interposer or a glass interposer with several dies bonded thereto.
The fifth application example is heterogeneous substrate bonding. For example, in the field of infrared image sensors, InGaAs is known as a high sensitivity material. Accordingly, if InGaAs is used for a sensor unit that receives light, and silicon capable of implementing high-speed processing is used for a logic circuit that extracts data, a high-sensitivity high-speed infrared image sensor can be manufactured. However, from InGaAs crystal, only substrates (wafers) whose diameter is as small as 4 inches are mass-produced, which is smaller than a mainstream silicon wafer having a size of 300 mm. Hence, a technique of bonding a separated InGaAs substrate to a 300-mm silicon wafer with a logic circuit formed thereon has been proposed. The bonding apparatus as one aspect of the present invention can also be applied to heterogeneous substrate bonding for bonding substrates made of different materials and having different sizes. When the bonding apparatus as one aspect of the present invention is applied to heterogeneous substrate bonding, the first object is a small piece of a material such as InGaAs, and the second object is a substrate such as a silicon wafer with a large diameter. Note that the small piece of the material is a slice of a crystal. The piece is preferably cut into a rectangular shape.
As shown in
The frame supply unit 7 includes a frame magazine 71 and a frame conveyance arm 72. The frame magazine 71 is formed to be detachable, and supplied from outside the apparatus while storing (mounted with) a plurality of dicing frames 5. The frame conveyance arm 72 takes out the dicing frame 5 from the frame magazine 71, and conveys (passes) the dicing frame 5 to the pickup unit 3. Further, the frame conveyance arm 72 conveys (returns) the dicing frame 5 completed with a bonding process from the pickup unit 3 to the frame magazine 71. Note that, in this embodiment, only one frame conveyance arm 72 conveys the dicing frame 5, but a plurality of frame conveyance arms 72 may relay the dicing frame 5. Furthermore, from the viewpoint of shortening the exchange time of the frame magazine 71 and the conveyance time of the dicing frame 5, the bonding apparatus BD may include a plurality of frame supply units 7.
The wafer supply unit 8 includes a wafer pod 81 and a wafer conveyance arm 82. The wafer pod 81 is formed to be detachable, and supplied from outside the apparatus while storing (mounted with) a plurality of wafers 6. The wafer conveyance arm 82 takes out the wafer 6 from the wafer pod 81, and conveys (passes) the wafer 6 to the bonding unit 4. Further, the wafer conveyance arm 82 conveys (returns) the wafer 6 completed with a bonding process from the bonding unit 4 to the wafer pod 81. Note that, in this embodiment, only one wafer conveyance arm 82 conveys the wafer 6, but a plurality of wafer conveyance arms 82 may relay the wafer 6. In order to increase the cleanliness, after the wafer 6 is loaded to the bonding apparatus BD, the wafer 6 may pass through a mechanism for cleaning the wafer 6 inside the bonding apparatus BD and a mechanism for executing preprocessing for bonding. Furthermore, from the viewpoint of shortening the exchange time of the wafer pod 81 and the conveyance time of the wafer 6, the bonding apparatus BD may include a plurality of wafer supply units 8.
In this embodiment, as shown in
The pickup unit 3 includes a pickup head 31 and a release head 32. The pickup unit 3 peels the die 51 to be bonded to the wafer 6 from the dicing tape by the release head 32, and holds the die 51 peeled from the dicing tape by sucking (chucking) it with the pickup head 31. The pickup head 31 rotates the die 51 by, for example, 180° and passes it to a bonding head 423 of the bonding unit 4.
The bonding unit 4 includes a stage base 41 and an upper base 42. A wafer stage 43 is mounted on the stage base 41. The wafer stage 43 is configured to be capable of driving concerning the X direction and the Y direction by a driving mechanism (not shown) such as a linear motor. The wafer stage 43 may be configured to be capable of driving concerning a rotation about an axis parallel to the Z direction. Instead of driving the wafer stage 43 concerning the rotation about the axis parallel to the Z direction, the bonding head 423 may drive the die 51 concerning the rotation about the axis parallel to the Z direction.
A die observation camera 431 is provided on the wafer stage 43. The die observation camera 431 obtains an image by capturing the die 51 held by the bonding head 423. From the image obtained by the die observation camera 431, a control unit 441 obtains the position of the feature point (portion) of the die 51 held by the bonding head 423, the outer diameter dimension of the die 51, and the height-direction (Z-direction) distances of a plurality of points of the measurement surface of the die 51 (the flatness of the die 51). In this manner, the die observation camera 431 cooperates with the control unit 441, thereby implementing a function of measuring the position of the feature point of the die 51, the outer diameter dimension of the die 51, and the flatness of the die 51.
A bar mirror 432 is provided on the wafer stage 43. The bar mirror 432 is used as the target of an interferometer 422. The wafer stage 43 holds the wafer 6 via a wafer chuck 433.
A wafer observation camera 421 is provided on the upper base 42. The wafer observation camera 421 obtains an image by capturing the wafer 6 held by the wafer stage 43 (wafer chuck 433). From the image obtained by the wafer observation camera 421, the control unit 441 obtains the position of the feature point (portion) of the die 61 of the wafer 6 held by the wafer stage 43, and the height-direction (Z-direction) distances of a plurality of points of the measurement surface of the wafer 6 (the flatness of the wafer 6). In this manner, the wafer observation camera 421 cooperates with the control unit 441, thereby implementing a function of measuring the position of the feature point (portion) of the die 61 of the wafer 6 and the flatness of the wafer 6. The wafer observation camera 421 may be a camera capable of measuring an element pattern or mark formed on the wafer or inside the wafer by using infrared light as measurement light.
The upper base 42 is further provided with the interferometer 422 for measuring the position of the wafer stage 43 using the bar mirror 432, and the bonding head 423 for holding the die 51 passed from the pickup head 31.
When bonding the die 51 to the wafer 6, for example, the bonding head 423 is driven downward (−Z direction) to bond the die 51 held by the bonding head 423 to the wafer 6 held by the wafer stage 43. Alternatively, the wafer stage 43 or the wafer chuck 433 may be driven upward (+Z direction) to bond the die 51 held by the bonding head 423 to the wafer 6 held by the wafer stage 43.
In this embodiment, the configuration is employed in which the pickup head 31 rotates the die 51 by 180° and passes it to the bonding head 423. However, by providing one or more die holding units between the pickup head 31 and the bonding head 423, the pickup head 31 may pass the die 51 to the die holding unit, and the die holding unit may pass the die 51 to the bonding head 423. Alternatively, a driving mechanism that drives the bonding head 423 may be provided and drive the bonding head 423 such that the bonding head 423 receives the die 51 from the pickup head 31. Note that, in order to improve productivity, the bonding apparatus BD may include a plurality of pickup heads, a plurality of release heads, and a plurality of bonding heads.
The bonding apparatus BD further includes the control unit 441 formed by an information processing apparatus (computer) including a CPU, a memory, and the like. The control unit 441 operates the bonding apparatus BD by comprehensively controlling the respective units of the bonding apparatus BD, for example, the pickup unit 3, the bonding unit 4, the frame supply unit 7, and the wafer supply unit 8 in accordance with a program stored in a memory unit. For example, in this embodiment, the control unit 441 functions as an obtainment unit that obtains rank information (to be described later), and a decision unit that decides the conveyance order of the dicing frames 5 and the conveyance order of the wafers 6.
A reference plate 434 is provided on the wafer stage 43 (upper surface thereof). In this embodiment, a plurality of marks 434a, 434b, and 434c are arranged (drawn) on the reference plate 434. The reference plate 434 is made of a material with a low thermal expansion coefficient, and the marks 434a, 434b, and 434c are drawn at a high position accuracy. For an example, the reference plate 434 is formed by a quartz substrate, and the marks 434a, 434b, and 434c are drawn thereon using the drawing method of a semiconductor lithography process. The reference plate 434 has a surface with almost the same height as the surface of the wafer 6, and can be observed by the wafer observation camera 421. A camera used to observe the reference plate 434 may separately be provided.
The wafer stage 43 may have a configuration that combines a coarse motion stage that is driven within a large range, and a fine motion stage that is accurately driven within a small range. In this configuration, the die observation camera 431, the bar mirrors 432a and 432b, the wafer chuck 433, and the reference plate 434 are provided on the fine motion stage to implement accurate positioning.
A method of guaranteeing the origin position, the magnification, and the directions (rotations) and orthogonality of the X-axis and the Y-axis of the wafer stage 43 using the reference plate 434 will be described here. The mark 434a is observed by the wafer observation camera 421, and the measured value (output value) of the interferometer when the mark 434a is located at the center of the image obtained by the wafer observation camera 421 is defined as the origin of the wafer stage 43. Next, the mark 434b is observed by the wafer observation camera 421, and the direction (rotation) of the Y-axis of the wafer stage 43 and the magnification in the Y direction are decided based on the measured value of the interferometer when the mark 434b is located at the center of the image obtained by the wafer observation camera 421. Next, the mark 434c is observed by the wafer observation camera 421, and the direction (rotation) of the X-axis of the wafer stage 43 and the magnification in the X direction are decided based on the measured value of the interferometer when the mark 434c is located at the center of the image obtained by the wafer observation camera 421.
In this manner, defining the direction from the mark 434b of the reference plate 434 to the mark 434a as the Y-axis of the bonding apparatus BD, and the direction from the mark 434c to the mark 434a as the X-axis of the bonding apparatus BD, the directions and orthogonality of the axes can be calibrated. Also, defining the interval between the mark 434b and the mark 434a as the scale reference of the Y-axis of the bonding apparatus BD and the interval between the mark 434c and the mark 434a as the scale reference of the X-axis of the bonding apparatus BD, calibration can be performed.
In the interferometer, the refractive index of the optical path changes due to variations of the atmospheric pressure and temperature, and this makes the measured value vary. Therefore, it is preferable to perform calibration at an arbitrary timing and guarantee the origin position, the magnification, and the directions (rotations) and orthogonality of the X-axis and the Y-axis of the wafer stage 43. To reduce the variation of the measured value of the interferometer, the space in which the wafer stage 43 is arranged may be covered with a temperature control chamber to control the temperature in the temperature control chamber.
In this embodiment, a case where the reference plate 434 provided on the wafer stage 43 is observed by the wafer observation camera 421 has been described, but the present invention is not limited thereto. For example, by providing the reference plate 434 on the upper base 42, and observing the reference plate 434 provided on the upper base 42 by the die observation camera 431, the origin position, the magnification, the directions (rotations) and orthogonality of the X-axis and the Y-axis of the wafer stage 43 may be guaranteed. Instead of performing calibration by observing the reference plate 434, for example, calibration may be performed by an abutting operation to a reference surface, or accurate positioning may be performed using a position measurement device such as a white interferometer that guarantees an absolute value.
With reference to
In step S101, rank information of the plurality of dicing frames 5 to be conveyed, which are stored in the frame magazine 71 and supplied to the bonding apparatus BD, and the plurality of wafers 6 to be conveyed, which are stored in the wafer pod 81 and supplied to the bonding apparatus BD, is obtained. In the manufacture of a semiconductor, after a semiconductor device is manufactured on a wafer, for example, a prober determines whether the device is a non-defective device or a defective device. In some cases, the device is classified (classified into multiple ranks) not only based on whether it is a non-defective device or a defective device, but also based on the performance (characteristic) such as speed. In this manner, the rank information is the data indicating the rank which is the classification determined from the class including the quality (data concerning the quality) of each of the dies 51 and 61. Hence, in this embodiment, the rank information, which includes data indicating ranks to which the respective dies 51 belong for each of the plurality of dicing frames 5 and data indicating ranks to which the respective dies 61 belong for each of the plurality of wafers 6, is obtained. As has been described above, the rank information is obtained from an external apparatus such as the prober different from the bonding apparatus BD before starting conveyance of the dicing frame 5 and the wafer 6.
A case in which two dicing frames D11 and D12 are stored in the frame magazine 71, and three wafers W11, W12, and W13 are stored in the wafer pod 81 will be described below as an example. In this case, the rank information obtained in step S101 includes data indicating the number of non-defective/defective dies 51 (the number of non-defective dies and the number of defective dies) for each of the dicing frames D11 and D12, as shown in
In step S102, based on the rank information obtained in step S101, the order (conveyance order) of conveying the dicing frames D11 and D12, and the order (conveyance order) of conveying the wafers W11, W12, and W13 are decided. For example, based on the rank information shown in
In step S103, in accordance with the conveyance orders decided in step S102, the dicing frames D11 and D12 are conveyed to the pickup unit 3, the wafers W11, W12, and W13 are conveyed to the bonding unit 4, and the die 51 is bonded to the die 61. At this time, the die 51 is bonded to the die 61 such that non-defective dies are bonded together and defective dies are bonded together. If bonding cannot be performed in the combination of non-defective dies or in the combination of defective dies, bonding is performed in a combination of the non-defective die 51 and the defective die 61 or in a combination of the defective die 51 and the non-defective die 61. Note that the bonding orders of the individual die 51 and die 61 are arbitrary as long as the number of bonds in the combination of non-defective dies and the number of bonds in the combination of defective dies are maximized.
In step S103, if all the dies 51 held by the dicing frame 5 have been bonded, this dicing frame 5 is exchanged to the next dicing frame 5. Similarly, if all the dies 61 formed on the wafer 6 have been bonded, this wafer 6 is exchanged to the next wafer 6. At this time, the dicing frame 5 and wafer 6 to be conveyed next follow the conveyance orders decided in step S102.
If the rank information shown in
In step S102, it is not always necessary to decide the conveyance order that maximizes the number of bonds in the combination of non-defective dies and the number of bonds in the combination of defective dies. In step S102, the conveyance order that can increase, as compared to a case where the conveyance order is not explicitly decided, the number of bonds in the combination of non-defective dies and the number of bonds in the combination of defective dies may be decided. Note that an arbitrary method is used as the specific method of deciding the conveyance order.
In this embodiment, the rank information has been described as two-level ranking data indicating the quality of each of the dies 51 and 61. However, as has been described above, the number of ranking levels may be an arbitrary number of three or more, and the criterion may be an arbitrary criterion other than the quality.
Further, in this embodiment, the combination of the same rank such as the combination of non-defective dies and the combination of the defective dies is prioritized, but it is not always necessary to prioritize the combination of the same rank. For example, within the range where a rank of the die 51 and the rank of the die 61 are similar (that is, bonding of die 51 and die 61 is allowed), a combination of arbitrary ranks may be prioritized. It is only required that the priority order of the combination of arbitrary ranks is uniquely decided.
With reference to
In step S1021, the dicing frames 5 and the wafers 6 to be processed are selected. More specifically, m dicing frames 5 satisfying “Cg≤the total number of the non-defective dies 51 held by m dicing frames 5” are selected from M dicing frames 5, and n=N wafers, that is, all the wafers 6 are selected. In a case where the condition is not satisfied even if M dicing frames 5 are selected, n wafers 6 satisfying “Dg≤the total number of the non-defective dies 61 formed on n wafers”, and m=M dicing frames 5, that is, all the dicing frames 5 are selected.
In step S1022, for n wafers 6 and m dicing frames 5 selected in step S1021, the conveyance orders are decided such that the wafers 6 and dicing frames 5 are conveyed in descending order of the number of non-defective dies. In other words, the conveyance order of n wafers 6 and the conveyance order of m dicing frames 5 are decided such that the wafers 6 are conveyed in descending order of the number of non-defective dies 61 and the dicing frames 5 are conveyed in descending order of the number of non-defective dies 51.
For example, consider a case where m dicing frames 5 are the dicing frames D11 and D12, n wafers 6 are wafers W11, W12, and W13, and their numbers of non-defective dies are as described by the rank information shown in
Note that, in this embodiment, the conveyance order of the wafers 6 and the conveyance order of the dicing frames 5 are decided such that they are conveyed in descending order of the number of non-defective dies, but the present invention is not limited to this. For example, in step S1022, for n wafers 6 and m dicing frames 5 selected in step S1021, the conveyance orders may be decided such that they are conveyed in descending order of the number of defective dies.
In this manner, according to this embodiment, it is possible to increase the number of bonds of the non-defective die 51 and the non-defective die 61 and the number of bonds of the defective die 51 and the defective die 61.
Accordingly, it is possible to suppress a decrease in yield (improve the yield) of a bonded object (device) obtained by bonding the die 51 and the die 61.
The first embodiment premises that each of the individual dicing frame 5 and wafer 6 is conveyed only once and used for bonding of the die 51 and the die 61. On the other hand, by performing bonding of the die 51 and the die 61 while exchanging the dicing frame 5 and the wafer 6, the number of bonds of the non-defective die 51 and the non-defective die 61 and the number of bonds of the defective die 51 and the defective die 61 can be maximized. However, as the number of exchanges of the dicing frame 5 and the wafer 6 increases, the overhead required for the exchanges deteriorates the productivity of the bonding apparatus BD. In this embodiment, a bonding method capable of increasing the number of bonds of a non-defective die 51 and a non-defective die 61 and the number of bonds of the defective die 51 and the defective die 61 without deteriorating the productivity of a bonding apparatus BD will be described.
In step S201, rank information of the plurality of dicing frames 5 to be conveyed, which are stored in a frame magazine 71 and supplied to the bonding apparatus BD, and the plurality of wafers 6 to be conveyed, which are stored in a wafer pod 81 and supplied to the bonding apparatus BD, is obtained. The rank information is obtained as in step S101 described in the first embodiment, so a detailed description will be omitted here.
In step S202, based on the rank information obtained in step S201, the conveyance order of the dicing frames 5 and the conveyance order of the wafers 6, the number of bonds of the die 51 and the die 61, and the exchange timing of each of the dicing frame 5 and the wafer 6 are decided. For example, the conveyance order of the dicing frames 5 and the conveyance order of the wafers 6 are decided such that the non-defective die 51 and the non-defective die 61 are bonded together and the defective die 51 and the defective die 61 are bonded together. Similarly, the number of bonding the die 51 and the die 61 (the number of bonds), and the timing of exchanging each of the dicing frame 5 and the wafer 6 (exchange timing) are decided such that the non-defective die 51 and the non-defective die 61 are bonded together and the defective die 51 and the defective die 61 are bonded together.
In step S203, in accordance with the conveyance orders and exchange timings decided in step S202, the dicing frame 5 and the wafer 6 are conveyed and exchanged, and the dies 51 are respectively bonded to the dies 61 so as to achieve the decided number of bonds. More specifically, in accordance with the conveyance orders decided in step S202, the dicing frame 5 is conveyed to a pickup unit 3, and the wafer 6 is conveyed to a bonding unit 4. Then, bonding of the non-defective die 51 to the non-defective die 61 and bonding of the defective die 51 to the defective die 61 are performed so as to achieve the number of bonds decided in step S202. Note that the bonding orders of the individual dies 51 and 61 are arbitrary as long as the number of bonds decided in step S202 is achieved. Then, in accordance with the exchange timings decided in step S202, the dicing frame 5 and the wafer 6 are exchanged. Note that the exchange timing is not limited to the timing when all the dies 51 held by the dicing frame 5 have been bonded or the timing when all the dies 61 formed on the wafer 6 have been bonded. The next dicing frame 5 and wafer 6 conveyed when exchanging the dicing frame 5 and wafer 6 follow the conveyance orders decided in step S202.
With reference to
In this embodiment, first, the dicing frame D21 and the wafer W21 are conveyed. Then, 18 (the number of bonds) non-defective dies 51 are respectively bonded to the non-defective dies 61, and 2 (the number of bonds) defective dies 51 are respectively bonded to the defective dies 61. At this point, all the dies 61 formed on the wafer W21 have been bonded, so the wafer W21 is exchanged to the wafer W22. On the other hand, the unbonded dies 51, which have not been used for bonding, still remain in the dicing frame D21, but the dicing frame D21 is also exchanged to the dicing frame D22 at the timing of exchanging the wafer W21 to the wafer W22 (that is, at the same timing as the wafer exchange).
Then, between the dicing frame D22 and the wafer W22, 17 (the number of bonds) non-defective dies 51 are respectively bonded to the non-defective dies 61, and three (the number of bonds) defective dies 51 are respectively bonded to the defective dies 61. At this point, all the dies 61 formed on the wafer W22 have been bonded, so the wafer W22 is exchanged to the wafer W23.
Then, between the dicing frame D22 and the wafer W23, seven (the number of bonds) non-defective dies 51 are respectively bonded to the non-defective dies 61, and three (the number of bonds) defective dies 51 are respectively bonded to the defective dies 61. At this point, all the dies 51 held by the dicing frame D22 have been bonded, so the dicing frame D22 is exchanged to the dicing frame D21.
Finally, between the dicing frame D21 and the wafer W23, five (the number of bonds) non-defective dies 51 are respectively bonded to the non-defective dies 61, and five (the number of bonds) defective dies 51 are respectively bonded to the defective dies 61.
By deciding, in the manner described above, the conveyance order of the dicing frames 5 and the conveyance order of the wafers 6, the number of bonds of the die 51 and the die 61, and the exchange timing of each of the dicing frame 5 and the wafer 6, all the non-defective dies 51 can be bonded to the non-defective dies 61, and all the defective dies 51 can be bonded to the defective dies 61.
In the example shown in
In step S202, it is not always necessary to decide the conveyance order and exchange timing that maximize the number of bonds in the combination of non-defective dies and the number of bonds in the combination of defective dies. In step S202, the conveyance order and exchange timing that can increase, as compared to a case where the conveyance order and exchange timing are not explicitly decided, the number of bonds in the combination of non-defective dies and the number of bonds in the combination of defective dies may be decided. Note that an arbitrary method is used as the specific method of deciding the conveyance order and exchange timing.
If yield is prioritized over productivity, it is not always necessary to decide the conveyance order and exchange timing that do not deteriorate productivity. For example, within the range of permissible productivity deterioration, the conveyance order and exchange timing may be decided which prioritize increasing the number of bonds in the combination of non-defective dies and the number of bonds in the combination of the defective dies. Note that an arbitrary method is used as the specific method of deciding the conveyance order and exchange timing.
In this embodiment, the rank information has been described as two-level ranking data indicating the quality of each of the dies 51 and 61. However, as has been described above, the number of ranking levels may be an arbitrary number of three or more, and the criterion may be an arbitrary criterion other than the quality.
The physical configuration of the bonding apparatus for implementing the bonding operation (
With reference to
In step S2021, the dicing frames 5 and the wafers 6 to be processed are selected. The dicing frames 5 and wafers 6 to be processed are selected as in step S1021 described in the first embodiment, so a detailed description will be omitted here. In the following description, n wafers 6 and m dicing frames 5 selected in step S2021 are to be processed.
In step S2022, repetitive (loop) processing is performed on n wafers 6 in descending order of the number of non-defective dies 61. The condition for ending the repetitive processing is that the processing has been performed on all of n wafers 6. In the repetitive processing, the wafer 6 of interest is referred to as a wafer Wi. Among the dies 61 formed on the wafer Wi, the number of unbonded non-defective dies, which have not been used for bonding, is indicated by Wig, and the number of unbonded defective dies, which have not been used for bonding, is indicated by Wib. Wig and Wib are managed as die information.
In step S2023, repetitive (loop) processing is performed on m dicing frames 5 in descending order of the number of non-defective dies 51. The condition for ending the repetitive processing is that all the dies 61 formed on the wafer Wi of interest are decided to be bonded, or all the dies 51 held by m dicing frames 5 are decided to be bonded, or both conditions are satisfied. In the repetitive processing, the dicing frame 5 of interest is referred to as a dicing frame Dj. Among the dies 51 held by the dicing frame Dj, the number of unbonded non-defective dies, which have not been used for bonding, is indicated by Djg, and the number of unbonded defective dies, which have not been used for bonding, is indicated by Djb. Djg and Djb are managed as die information.
In step S2024, the wafer Wi and the dicing frame Dj are loaded on a wafer conveyance order queue and a dicing frame conveyance order queue, respectively, and the loading order on each conveyance order queue is decided as the conveyance order. Regarding the dicing frame Dj, the same individual may be the dicing frame of interest (target object) over multiple repetitive processing operations. If the dicing frame already loaded on the trailing end of the conveyance order queue is the same individual as the dicing frame Dj of interest in the current repetitive processing, the dicing frame Dj is not loaded on the conveyance order queue. Then, for the wafer Wi, the value of the unbonded non-defective die count Wig (that is, die information) is updated assuming that bonding has been performed. More specifically, if “Wig≥Djg”, the value is updated to “Wig=Wig−Djg”, and if “Wig<Djg”, the value is updated to “0”. The value of the unbonded defective die count Wib (that is, die information) is similarly updated. More specifically, if “Wib≥Djb”, the value is updated to “Wib=Wib−Djb”, and if “Wib<Djb”, the value is updated to “0”. Similarly, for the dicing frame Dj, the value of the unbonded non-defective die count Djg (that is, die information) is updated assuming that bonding has been performed. More specifically, if “Wig≥Djg”, the value is updated to “0”, and if “Wig<Djg”, the value is updated to “Djg=Djg−Wig”. The value of the unbonded defective die count Djb (that is, die information) is similarly updated. More specifically, if “Wib≥Djb”, the value is updated to “0”, and if “Wib<Djb”, the value is updated to “Djb=Djb−Wib”.
The processing in step S2024 means the following three points.
In step S2025, it is determined whether a dicing frame Dj+1 of interest (to be processed) in the next repetitive processing is the same individual as the dicing frame Dj of interest in the current repetitive processing (that is, whether the dicing frame Dj of the same individual is selected). Since the value of the unbonded non-defective die count Djg is updated in step S2024, in the next repetitive processing, the dicing frame Dj of the same individual may become the dicing frame of interest. This means that, in the next repetitive processing, if the dicing frame Dj of the same individual is selected as the dicing frame of interest, bonding of non-defective dies and bonding of defective dies cannot be performed. Therefore, if the dicing frame Dj of the same individual is selected, the process transitions to step S2026. On the other hand, if the dicing frame Dj of the same individual is not selected, the process transitions to the next repetitive processing in step S2023.
In step S2026, since bonding in a combination of non-defective dies and bonding in a combination of defective dies cannot be performed between the wafer Wi and the dicing frame Dj, it is decided to perform bonding in a combination of a non-defective die and a defective die. Then, the values of the unbonded non-defective die count Wig, the unbonded defective die count Wib, the unbonded non-defective die count Djg, and the unbonded defective die count Djb (that is, die information) are updated assuming that bonding in the combination of the non-defective die and the defective die has been performed. More specifically, for Wig, if “Wig≥Djb”, the value is updated to “Wig=Wig−Djb”, and if “Wig<Djb”, the value is updated to “0”. For Wib, if “Wib≥Djg”, the value is updated to “Wib=Wib−Djg”, and if “Wib<Djg”, the value is updated to “0”. Similarly, for Djg, if “Wib≥Djg”, the value is updated to “0”, and if “Wib<Djg”, the value is updated to “Djg=Djg−Wib”. For Djb, if “Wig≥Djb”, the value is updated to “0”, and if “Wig<Djb”, the value is updated to “Djb=Djb−Wig”. If the processing in step S2026 ends, the process transitions to the next repetitive processing in step S2023.
In the repetitive processing in steps S2022 to S2026, all the dies 61 formed on n wafers 6 are decided to be bonded, and thus the processing in step S202 is completed.
In a case where the number of non-defective/defective dies of each dicing frame 5 and that of each wafer 6 supplied to the bonding apparatus BD are as shown in
In this manner, according to this embodiment, it is possible to increase the number of bonds of the non-defective die 51 and the non-defective die 61 and the number of bonds of the defective die 51 and the defective die 61. Accordingly, it is possible to suppress a decrease in yield (improve the yield) of a bonded object (device) obtained by bonding the die 51 and the die 61.
Depending on the number of non-defective/defective dies 51 held by a dicing frame 5 and the number of non-defective/defective dies 61 formed on a wafer 6, even the processing (
Since the number of dies 51 held by a dicing frame 5 is generally different from the number of dies 61 (the dies to which the dies 51 are bonded) formed on a wafer 6, in a bonding process, the exchange timing of the dicing frame 5 does not synchronize with the exchange timing of the wafer 6. In addition, since the number of the dicing frames 5 stored in a frame magazine 71 is different from the number of the wafers 6 stored in a wafer pod 81, the exchange timing of the frame magazine 71 does not synchronize with the exchange timing of the wafer pod 81. Hence, at the timing when all the dies 51 held by all the dicing frames 5 stored in and supplied from the frame magazine 71 have been bonded, there may be unbonded dies 61 remaining on the wafer 6 stored in and supplied from the wafer pod 81. In this case, the dies 51 held by the dicing frame 5 stored in the next frame magazine 71 to be supplied to a bonding apparatus BD may be bonded to the unbonded dies 61 remaining on the wafer 6. In this case, the processing (
In this manner, according to this embodiment, it is possible to increase the number of bonds of the non-defective die 51 and the non-defective die 61 and the number of bonds of the defective die 51 and the defective die 61. Accordingly, it is possible to suppress a decrease in yield (improve the yield) of a bonded object (device) obtained by bonding the die 51 and the die 61.
Assume a case where a bonding apparatus BD includes a plurality of frame supply units 7 and a plurality of wafer supply units 8. In this case, in the bonding apparatus BD, while performing a bonding process of bonding a die 51 held by a dicing frame 5 to a die 61 formed on a wafer 6, a new frame magazine 71 or a new wafer pod 81 may be supplied. In this case, the processing (
So far, the description has been given premising that all the dies 51 held by the dicing frames 5 supplied to the bonding apparatus BD and all the dies 61 formed on the wafers 6 supplied to the bonding apparatus BD are bonded. The reason why the die 51 is bonded to the defective die 61 is that, as has been described above, it is necessary to bond (arrange) the die 51 to even the defective die 61 to suppress a deterioration in uniformity in the molding and bonding processes. On the other hand, it is not always necessary to use all of the defective dies 51 for bonding. For example, assume a case where, at the timing when all dies 61 formed on all wafers 6 supplied to a bonding apparatus BD have been bonded, unbonded dies 51 not bonded to the dies 61 remain in the dicing frame 5 simultaneously supplied to the bonding apparatus BD. In this case, if all of the unbonded dies 51 remaining in the dicing frame 5 are defective (predetermined rank), all of them may not be used for bonding to the dies 61. Then, the dicing frame 5 with the unbonded dies 51 remaining therein is returned to a frame magazine 71. The frame magazine 71 may be exchanged, or the dicing frame may be unloaded from the bonding apparatus BD.
In addition to not using the defective dies 51 for bonding, which eventually remain in the dicing frame 5, before deciding the conveyance orders of the dicing frames 5 and the wafers 6, a certain number of defective dies 51 may be excluded from the parameter, and then the conveyance order may be decided.
In this embodiment, the die 51 not used for bonding has been described as the defective die. However, in a case of classifying into three or more ranks, the die 51 belonging to the rank equal to or lower than a predetermined rank may not be used for bonding.
In the first and second embodiments, the example has been described in which the rank information obtained from the external apparatus such as a prober is employed as the index of the priority order. However, the rank information can be updated, as appropriate. For example, even if a die is determined in advance as a non-defective die by the prober, a foreign substance or the like may adhere during conveyance to a bonding apparatus BD and cause a bonding defect. In such a case, in addition to the rank information, foreign substance information indicating presence/absence of adhesion of a foreign substance to the die may be obtained. Even if a die is determined to be non-defective, if a foreign substance adheres to it, the rank information may be updated to indicate “defective die”. Note that the foreign substance information may be an image obtained by capturing the die, and the adhesion of a foreign substance may be determined from the image.
Instead of directly using the rank information obtained from the external apparatus, the rank information may be updated using another information. For example, there is a case where, in order to improve productivity, dies to pre-measure the rank are thinned out, thereby obtaining rank information including the ranks of some dies in the dicing frame and wafer. In this case, the rank of individual die may be decided by statistically processing the ranks of the dies included in the rank information to analogize and interpolate the ranks of other dies. The information used to decide the final rank and the method used to decide the rank are arbitrary.
A method of manufacturing an article (a semiconductor IC element, a liquid crystal element, a MEMS, or the like) using the bonding apparatus BD in the above-described embodiments will be described. The manufacturing method includes a step of preparing a plurality of carriers (dicing frames 5) each holding a plurality of separated first objects (dies 51), and a step of preparing a plurality of substrates (wafers 6) with a plurality of second objects (dies 61) formed on each substrate. The manufacturing method further includes a step of forming a bonded object by bonding the first object and the second object using a bonding apparatus BD (bonding method (bonding operation)), and a step of manufacturing an article by processing the bonded object in another known process. The other known process includes probing, dicing, bonding, packaging, and the like. The article manufacturing method according to this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article, as compared to conventional methods.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent application No. 2023-118516 filed on Jul. 20, 2023, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-118516 | Jul 2023 | JP | national |
