The present application claims priority to Chinese Patent Application No. 2020102164393, entitled “SEMICONDUCTOR STRUCTURE” and filed with the China National Intellectual Property Administration on Mar. 25, 2020, the entire contents of which are incorporated herein by reference.
The present invention relates to the field of semiconductors, in particular to a semiconductor structure.
With the continuous development of semiconductor technologies, people's requirements for chip preparation technologies are also constantly increasing. At present, in a chip preparation process, the process flow of coating, developing, etching, doping, or the like is carried out on a wafer to form a die; then a pin test is performed on the die to confirm the device performance of the die; next, the die passing the pin test is diced and packaged; and finally the packaged chip is subjected to the final performance test.
However, when the wafer is diced and packaged, it is easy to cause mechanical damage to the die due to excessive dicing pressure of a dicing knife and excessive packaging pressure. Moreover, when the die has a mechanical damage and the mechanical damage is severe, a structure of an internal chip circuit will be damaged, resulting in partial or even complete failure of the device's functions; when the mechanical damage is small, on the other hand, water molecules and oxygen molecules will enter the internal chip circuit of the die from the position of the mechanical damage, thereby oxidizing or corroding metal wires in the internal chip circuit and further causing the internal chip circuit to fail.
According to various embodiments, a semiconductor structure is provided.
A semiconductor structure is disposed on a substrate surface of a die and the die includes an internal chip circuit. The semiconductor structure includes:
a first guard ring, disposed around the internal chip circuit and configured to suppress a mechanical damage to the die; and
a second guard ring, disposed around the internal chip circuit and configured to suppress the mechanical damage and to monitor a magnitude of the mechanical damage;
wherein the second guard ring includes a plurality of first structures and a plurality of second structures, and the first structure and the second structure have different mechanical strengths and different resistivities.
The above-mentioned semiconductor structure is disposed on the substrate surface of the die, and the die includes an internal chip circuit. The semiconductor structure includes: a first guard ring, annularly disposed around the internal chip circuit and configured to suppress a mechanical damage to the die; a second guard ring, annularly disposed around the internal chip circuit and configured to suppress the mechanical damage and to monitor the magnitude of the mechanical damage; wherein the second guard ring includes a plurality of first structures and a plurality of second structures, the first structure and the second structure have different mechanical strengths and different resistivities. Since the first guard ring and the second guard ring provide double protection for the internal chip circuit, the problem of insufficient resistance of a single guard ring to the deformation of the substrate is solved, and the mechanical damage to the die is effectively suppressed, thereby improving the reliability of the guard rings and the internal chip circuit; moreover, the mechanical damage condition of the die can be obtained in real time by monitoring the magnitude of the mechanical damage, so as to adjust the dicing and protection strategy of the die in time to improve a processing yield of the chip.
In order to better describe and illustrate embodiments of the present disclosure, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the accompanying drawings should not be considered as limitations on the scope of any of the invention-creations, the embodiments described hereinafter, and the preferred embodiments of the present disclosure.
For easy understanding of the present disclosure, a more comprehensive description of the present disclosure will be given below with reference to the relevant accompanying drawings. Preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the contents disclosed in the present disclosure more thorough and comprehensive.
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as are commonly understood by those skilled in the art. The terms used herein in the specification of the present disclosure are for the purpose of describing specific embodiments only but not intended to limit the present disclosure. The term “and/or” used herein includes any and all combinations of one or more related listed items.
In the description of the present disclosure, it should be understood that the orientation or position relationship indicated by the terms “upper”, “lower”, “vertical”, “horizontal”, “inner”, “outer”, or the like are based on the orientation or position relationship shown in the accompanying drawings and are intended to facilitate the description of the present disclosure and simplify the description only, rather than indicating or implying that the apparatus or element referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore are not to be interpreted as limiting the present disclosure.
The first guard ring 100 is annularly disposed around the internal chip circuit 301 and configured to suppress a mechanical damage to the die 300.
The mechanical damage of the die 300 refers to a crack caused by a deformation of the substrate of the die 300. The temperature and humidity changes in the environment where the die 300 is located, as well as the dicing and packaging processes all have the risk of causing the mechanical damage.
Specifically, the first guard ring 100 is disposed between the internal chip circuit 301 and a dicing lane 302. The first guard ring 100 is of a closed ring structure and has a large ring width and a high mechanical strength. The first guard ring 100, on the one hand, can eliminate an internal stress of the die 300 caused by the dicing and packaging process, thereby reducing the probability of the mechanical damage to the die 300; on the other hand, when the die 300 is mechanically damaged, the high mechanical strength of the first guard ring 100 can suppress the further spread and development of the mechanical damage. Moreover, after the die 300 is packaged, the first guard ring 100 can also prevent the intrusion of external water molecules and oxygen molecules, thereby avoiding oxidation or corrosion of the metal lines of the internal chip circuit, and improving the reliability and stability of the packaged chip.
The second guard ring 200 is annularly disposed around the internal chip circuit 301 and configured to suppress the mechanical damage and to monitor the magnitude of the mechanical damage.
The magnitude of the mechanical damage includes the length and width of the crack.
Specifically, the second guard ring 200 is also disposed between the internal chip circuit 301 and the dicing lane 302, wherein the second guard ring 200 includes a plurality of first structures and a plurality of second structures, and the first structure and the second structure have different mechanical strengths and different resistivities. The part with a high mechanical strength in the second guard ring 200 has a stronger ability to resist the internal stress and is configured to suppress the mechanical damage; when the mechanical damage to the second guard ring 200 causes the change in the resistance value of the internal structure, the resistance value of the part with a high resistivity changes more than that of the part with a low resistivity. Therefore, the part with a high resistivity can more accurately reflect the magnitude of the mechanical damage, so as to realize real-time monitoring to the mechanical damage.
The above-mentioned semiconductor structure is disposed on a substrate surface of the die 300, and the die 300 includes an internal chip circuit 301. The semiconductor structure includes: a first guard ring 100, annularly disposed around the internal chip circuit 301 and configured to suppress the mechanical damage of the die 300; and a second guard ring 200, annularly disposed around the internal chip circuit 301 and configured to suppress the mechanical damage and to monitor the magnitude of the mechanical damage; wherein the second guard ring 200 includes a plurality of first structures and a plurality of second structures, and the first structure and the second structure have different mechanical strengths and different resistivities. Since the first guard ring 100 and the second guard ring 200 provide double protection for the internal chip circuit 301, the problem of insufficient resistance of a single guard ring to the deformation of the substrate is solved, and the mechanical damage to the die 300 is effectively suppressed, thereby improving the reliability of the guard rings and the internal chip circuit 301; moreover, the mechanical damage condition of the die 300 can be obtained in real time by monitoring the magnitude of the mechanical damage, so that the dicing and protection strategies of the die 300 can be adjusted in time to improve the processing yield of the chip.
It should be noted that projections of the first guard ring 100 and the second guard ring 200 on the substrate do not overlap with each other. As shown in
Further, the first guard ring 100 may also include a plurality of sub guard rings 110. Specifically, when the size of the die 300 is large, for example, 100 mm2, the die 300 is more prone to a mechanical damage, so three sub guard rings 110 can be disposed to provide better protection for the internal chip circuit; when the size of the die 300 is small, for example, 10 mm2, the die 300 is not prone to a mechanical damage, so only two sub guard rings 110 can be disposed, thereby reducing an occupied area of the first guard ring 100 on the substrate surface.
In an embodiment, the first guard ring 100 is disposed in contact with a surface of an active region of the substrate, and the active region may be N-type or P-type.
Specifically, a rectangular path drawn by the dashed line in
In an embodiment, the mechanical strength of the first structure 210 is greater than the mechanical strength of the second structure 220, and the first structure 210 is configured to suppress the mechanical damage. It can be understood that the mechanical strength of a structure is determined by the characteristics of its material itself and the composition characteristics of the structure. Therefore, the first structure 210 can be made of a material with a high shear resistance coefficient and a high tensile strength coefficient to improve the mechanical strength of the first structure 210; the first structure 210 with a large cross-sectional area may also be formed to improve the mechanical strength of the first structure 210.
In an embodiment, the resistivity of the second structure 220 is greater than the resistivity of the first structure 210, and the resistance value of the second structure 220 matches the magnitude of the mechanical damage. It can be understood that the resistivity of a structure is determined by the characteristics of its material itself and the composition characteristics of the structure, or the like Therefore, the second structure 220 can be made of a material with a high resistivity to increase the resistivity of the second structure 220; the second structure 220 with a small cross-sectional area or a long length may also be formed to improve the resistivity of the second structure 220. The expression that the resistance value of the second structure 220 matches the magnitude of the mechanical damage means that the resistance value of the second structure 220 has a correlation with the magnitude of the mechanical damage. Specifically, the correlation may be a positive correlation, that is, the larger the width and/or the length of the crack, the higher the resistance value of the second structure 220; the correlation may also be a negative correlation, that is, the larger the width and/or the length of the crack, the lower the resistance value of the second structure 220.
In an embodiment, as shown in
Further, the monitoring module has a monitoring function and a warning function. The monitoring function is used to obtain the resistance information of the second guard ring 200 in real time, and the warning function is used to send a warning signal according to a preset warning condition and the resistance information. For example, the preset warning condition is that the real-time resistance value exceeds a resistance threshold. When the real-time resistance value is less than the resistance threshold, no warning signal will be sent; when the real-time resistance value is not less than the resistance threshold, a warning signal will be sent to remind an operator, a dicing device or a packaging device to adjust the die dicing and protection strategies.
In an example, the monitoring module is an external resistance test device. When the external resistance test device is used to monitor the second guard ring 200, a test probe of the resistance test device is connected to the lead-out terminals 202 to obtain the resistance information of the second guard ring 200. The external resistance test device can be compatible with a larger data storage space, and save resistance information in the data storage space for a large time range, so that more reference data can be provided for dicing and packaging process control over other dies.
In another example, the monitoring module is a monitoring circuit disposed on the substrate surface. Further, the monitoring circuit can be integrated in the internal chip circuit 301, or can be independently disposed outside the internal chip circuit 301. The monitoring circuit disposed on the substrate surface is not limited by the test location and the external test device, so the resistance information of the second guard ring 200 can be monitored more flexibly.
In the embodiment shown in
In other embodiments, the second guard ring 200 may also be provided with a plurality of openings 201, two lead-out terminals 202 are disposed at each opening 201, and the second guard ring 200 is divided into a plurality of guard segments by the plurality of openings 201. Further, a plurality of guard segments can be disposed in areas prone to mechanical damage, such as the corner areas of the die 300, and one guard segment can be disposed in an area not prone to mechanical damage, such as a straight edge of the die 300, so as to monitor the mechanical damage more accurately.
In an embodiment, both the first structure 210 and the second structure 220 are laminated structures and include the same conductor structure. The same conductor structure refers to such a conductor structure that an arrangement order and material of all the functional layers in the device are the same, but the same conductor structure does not limit the specific sizes of the first structure 210 and the second structure 220, that is, the conductor structure of the first structure 210 and the second structure 220 may be different in size.
In an embodiment, each conductor structure includes: at least two metal layers; and a through hole layer disposed between the two adjacent metal layers and configured to connect the adjacent metal layers. Specifically, the two adjacent metal layers at least partially overlap in the vertical direction, and the through hole layer is disposed at an overlapped portion to conduct the adjacent metal layers.
In one embodiment, as shown in
In an embodiment, the through hole 236 may be of a groove structure.
The first conductive structure includes the first bottom metal layer 211, a first middle metal layer 212, a first top metal layer 213, as well as first through hole layers 214 disposed between two adjacent metal layers, wherein the first bottom metal layer 211, the first middle metal layer 212, and the first top metal layer 213 are laminated in sequence. The first top metal layer 211 and the first middle metal layer 212 may be made of one of aluminum and copper, the first bottom metal layer 211 may be made of one of tungsten, aluminum, and copper, and the conductor layer 203 may be made of polysilicon.
In this embodiment, through the above-mentioned first structure 210 and second structure 220, the second guard ring 200 with a high mechanical strength and accurate mechanical damage monitoring is realized. It should be noted that the two first top metal layers 213 can be used as lead-out terminals 202 connected to the monitoring module, or the two first bottom metal layers 211 can also be used as lead-out terminals 202 connected to the monitoring module. The positions of the lead-out terminals 202 in the first structures 210 and the second structures 220 are not specifically defined in this embodiment. The above-mentioned arrangements of the lead-out terminals 202 can both accurately monitor the mechanical damage of the die 300.
In an embodiment, as shown in
It should be noted that the above specific numerical values are only for illustration, and do not constitute a limitation on the semiconductor structure involved in the present disclosure.
S100: providing a substrate provided with an isolation structure and an active region;
S200: forming a substrate contact hole 215, a first conductor contact hole 216 and a second conductor contact hole 225 in the surface of the substrate, wherein the top of the substrate contact hole 215 and the first conductor contact hole 216 are flush; and
S300: forming a first conductive structure on the surface with the substrate contact hole 215 and the first conductor contact hole 216, and forming a second conductive structure on the surface with the second conductor contact hole 225.
In an embodiment, both the first conductive structure and the second conductive structure include two metal layers, that is, the first conductive structure includes a first bottom metal layer 211 and a first top metal layer 213, and the second conductive structure includes a second bottom metal layer 221 and a second top metal layer 223.
S310: forming a first bottom metal layer 211 on the surface with the substrate contact hole 215 and the first conductor contact hole 216 and forming a second bottom metal layer 221 on the surface with the second conductor contact hole 225;
S320: forming a first through hole layer 214 in the surface of the first bottom metal layer 211 and forming a second through hole layer 224 in the surface of the second bottom metal layer 221; and
S330: forming a first top metal layer 213 on the surface of the first through hole layer 214 and forming a second top metal layer 223 on the surface of the second through hole layer 224, wherein the first top metal layer 213 is connected with the second top metal layer 223.
It should be understood that although the various steps in the flowcharts of
Technical features of the above embodiments may be combined randomly. To make descriptions brief, not all possible combinations of the technical features in the embodiments are described. Therefore, as long as there is no contradiction between the combinations of the technical features, they should all be considered as scopes disclosed in the specification.
The above embodiments only describe several implementations of the present disclosure, and their description is specific and detailed, but cannot therefore be understood as a limitation on the patent scope of the present disclosure. It should be noted that those of ordinary skill in the art may further make variations and improvements without departing from the conception of the present disclosure, and these all fall within the protection scope of the present disclosure. Therefore, the patent protection scope of the present disclosure should be subject to the appended claims.
Number | Date | Country | Kind |
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202010216439.3 | Mar 2020 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2021/081445 | 3/18/2021 | WO |