In microelectromechanical system (MEMS) device manufacturing, bonding is frequently a necessary step to join two portions of a device, for example, during a packaging step. Traditional bonding typically includes inserting a bonding material between the two portions of the device and then adhering the two portions with the bonding material. The inventors have discovered that the traditional approaches are deficient and lead to unreliable MEMS devices.
When bonding two materials in MEMS devices (e.g., bonding glass to silicon), a coefficient of thermal expansion (CTE) mismatch can lead to alignment deviations, which can lead to bonding or other manufacturing errors. The deviations can stem from different shrinkage rates (caused by the different CTEs) after the layers are heated for bonding (up to 350 C in some processes) and allowed to cool. These deviations increase as manufacturing scale increases—a panel level manufacturing process with a CTE mismatch will experience more manufacturing errors than the same process at wafer scale.
In another example, the inventors discovered additional deficiencies in bonding two portions of a MEMS device. For example, vacuum packaging (using solder (e.g., solder preforms, deposited solder) as a bonding material, for example) commonly suffers from excess bonding material being squeezed out from between the two bonding interfaces during the bonding process. For example, since solder preforms must be thick enough to survive mechanical handling, they frequently have a minimum thickness and, hence, minimum volume; for this reason, the amount of excess material, when bonding using preforms, is especially problematic when the minimum volume is greater than the volume needed in a manufacturing process. The excess solder volume is squeezed-out from the bonding region and can adversely affect the reliability of a MEMS device if the excess solder is captured within the sealed volume, as the excess solder can damage and/or destroy the devices inside the sealed volume. Excess solder outside the cavity can also be detrimental. For example, squeezed out solder can remain between a die, which can damage wafer dicing blades, leading to lower manufacturing yield.
Some embodiments include methods of manufacturing a plurality of MEMS devices, each device including a first material and a second material with different CTE. The method includes providing a carrier with substantially equal CTE as the first material, the carrier comprising a plurality of cavities. The method also includes positioning a plurality of components in respective cavities of the carrier, the components comprising the second material. In some embodiments, the method includes positioning a layer of the first material on the second material components. In some embodiments, the method includes bonding the first material layer and the second material components. The method also includes removing the carrier and singulating the first material layer to produce the plurality of MEMS devices. In some embodiments, the first and second material are selected from glass and silicon.
Advantageously, methods of manufacturing described herein reduce manufacturing errors caused by layers' CTE mismatch. For example, methods described herein reduce the result of CTE mismatch (e.g., between a glass layer of a MEMS device and a silicon component of the MEMS device) to the width of the MEMS device. This advantageously provides for better aligned and bonded MEMS devices, for better scaling, and also allows for freedom in selecting material combinations (e.g., glass and silicon) for MEMS devices.
Some embodiments include a method of manufacturing a MEMS device, where the method includes a first step of providing a first portion of the device, a second step in which grooves are added to the first portion at a bond region of the device, a third step of aligning a second portion of the device with the first portion, a fourth step in which the first portion and second portion are moved toward each other, and a fifth step wherein the first and second portions are bonded at the bond region. Advantageously, the grooves can provide for a tight bond while reducing potentially harmful spillover from the bonding region to the electromechanical components of the MEMS device. Accordingly, reliability of the MEMS devices is improved. In some embodiments, one or more of the first through fifth steps are performed in a vacuum. In some embodiments, some steps are performed in a vacuum (e.g., the third through fifth steps) and other steps may not be.
Some embodiments include a method of manufacturing a plurality of MEMS devices, where the method includes: a step of providing a plurality of first electromechanical components; a step in which a carrier is provided, the carrier including a plurality of positions, each associated with a respective one of the plurality of first electromechanical components; a step of identifying a defective component in the plurality of first electromechanical components; a step of providing a plurality of second electromechanical components; a step of positioning the plurality of second electromechanical components at respective positions on the carrier but not a position associated with the defective electromechanical component; a step in which respective pairs of first and second electromechanical components are bonded; and (optional) a step of singulating the respective pairs of first and second electromechanical components to produce the plurality of MEMS devices. Advantageously, such methods may reduce wasted components by reducing the number of first components bonded to inoperable second components.
In the following description of embodiments, reference is made to the accompanying drawings which form a part hereof, and in which it is shown by way of illustration specific embodiments which can be practiced. It is to be understood that other embodiments can be used and structural changes can be made without departing from the scope of the disclosed embodiments.
An exemplary method of manufacturing a plurality of MEMS devices will now be described with respect to
Method 100 includes step 102, providing a carrier with substantially equal CTE as the first material, the carrier including a plurality of cavities. The method continues with step 104, positioning a plurality of components in respective cavities of the carrier, each component including the second material. Step 106 includes positioning a layer of the first material on the second material components. Method 100 also includes step 108, bonding the first material layer and the second material components, and step 110, removing the carrier. Method 112 continues with singulating the first material layer to produce the plurality of MEMS devices.
Method 100 can be performed at any scale, including panel scale manufacturing, wafer scale manufacturing, etc. In some embodiments, two layers in a manufacturing process can be understood to have “substantially equal CTE” a difference in respective CTEs does not cause the layers to deviate, when heat for bonding is applied/removed, such that bonding and/or alignment of the second material components and first material layer fall outside manufacturing tolerances. Tolerances will depend on the particular application. For example, the tolerance may be 50 micron deviation of a device cover at an 8 inch wafer edge at 300 C bonding temperature. Two materials can be understood to have “different CTE” when they do not have substantially equal CTE.
Advantageously, methods of manufacturing described herein reduce manufacturing errors caused by layers' CTE mismatch. For example, methods described herein reduce the result of CTE mismatch (e.g., between a glass layer of a MEMS device and a silicon component of the MEMS device) to the width of the MEMS device. This advantageously provides for better aligned and bonded MEMS devices, and also allows for freedom in selecting combinations (e.g., glass and silicon) for MEMS devices.
Further, methods described herein may also improve the accuracy of singulating techniques and improve manufacturability by not requiring specialty equipment. For example, embodiments herein do not require infrared camera to remove portions of a second material (e.g., silicon) before singulating the devices. Embodiments herein also advantageously increase yield and reduce manufacturing costs. For example, embodiments here reduce or remove the need to dice through 2 substrates simultaneously (or the need for two partial cuts on either side).
In some embodiments, providing a carrier includes providing a layer of material with substantially equal CTE as the first material. In some embodiments, providing a carrier includes providing a carrier layer of the first material. In some embodiments, the first material is glass, and providing the carrier includes providing a different glass, but one that has substantially equal CTE as a glass used in the MEMS devices. In some embodiments, providing a carrier includes providing a ceramic material (e.g., Al2O3) or a metal (e.g., Kovar).
In some embodiments, providing a carrier includes providing a first carrier layer, providing a second carrier layer, bonding the first and second carrier layers, and removing material from one or both of the first and second carrier layers to create the plurality of cavities. In some embodiments, removing material from one or both of the first and second layers includes providing an etch stop layer between the layers and etching one or both of the first and second layers to the etch stop. In other embodiments, material is removed from one or both of the first and second layers before the layers are bonded.
In some embodiments, providing a carrier includes providing cavities of 0.5 mm depth. In some embodiments, the cavity is 24-27 mm wide and 14-16 mm long. For example, a cavity could be 24 mm×16 mm×0.5 mm or another could be 27 mm×14 mm×0.5 mm.
In some embodiments, the carrier is a round wafer or a square wafer. The wafer can be, for example, 4 inches, 6 inches, 8 inches, or 12 inches. In some embodiments, the carrier is panel-sized.
In some embodiments, the second material is silicon and the first material is glass. In such embodiments, the CTE mismatch may be 0.3-0.8 ppm.
In some embodiments, positioning a plurality of components includes applying a vacuum to the components to secure the components to the carrier. In some embodiments, applying a vacuum includes applying a vacuum to the components through a channel in the carrier, e.g., channel 224. In some embodiments, a vacuum is not applied to the components. In such embodiments, channel 224 may not be added to carrier 220. In some embodiments, a vacuum is applied through channel 224 for the purpose of evacuating a region under the components 230. Such channels may advantageously allow for a vacuum to be applied after the components 230 are positioned on carrier 220, removing air that may get trapped between the components 230 and the carrier 220.
In some embodiments, the components correspond to covers in the plurality of MEMS devices.
In some embodiments, each component includes side walls with a metalized surface. In some embodiments, each component's sidewalls define a cavity in the second material component. In some embodiments, the components are provided to the manufacturing process with the cavity already defined. In other embodiments, the cavity is defined while the components are positioned in the cavities of the carrier. Similarly, the metalized surfaces on the components' sidewalls may be provided before positioning the components in the respective cavities or may be added after the components are positioned in the cavities of the carrier. In some embodiments, bonding the first material layer and the second material components includes depositing bonding components on the metalized surfaces. In such embodiments, the bonding components can include solder preforms. In some embodiments, the bonding components can include deposited solder. In some embodiments, the sidewalls are approximately 1-2 mm wide (in such embodiments, the bonding components (e.g., solder preforms, deposited solder) described herein may be 500 microns wide). In some embodiments, the sidewalls are on the order of a few hundred microns. In some embodiments, the second material components can be approximately 725 microns thick (as measured in a direction orthogonal to a plane of the first material carrier).
As described below, methods of manufacturing can include, after positioning the first material layer, bonding the first material layer and the second material components. In the example of arrangement 206, bonding components (e.g., solder preforms, deposited solder) were deposited for the bonding. In some embodiments, bonding the first material layer (described below with respect to arrangement 208) and the second material components includes growing bonding components by deposition (e.g., electroplating or vacuum deposition). In some embodiments, bonding the first material layer and the second material components includes increasing the temperature of the arrangement to effectuate bonding. In some embodiments, bonding may be effectuated at about 350 C. In some embodiments, the temperature is increased to approximately 300 C. In such embodiments, the bonding component includes AuSn. In some embodiments, the temperature mismatch may play a greater role, such as in Au—Au thermocompression bonding.
In some embodiments, prior to bonding the first material layer and second material components, a method includes moving the second material components toward the first material layer. This may advantageously allow for efficient bonding of the first and second materials where the height(s) (as measured in a direction orthogonal to a plane of the first material carrier) of the second material components is(are) shorter than the depth (measured in the direction orthogonal to the plane of the first material carrier) of the cavities and/or the second material components have different heights. In such embodiments, a force is applied to move the components toward the material layer. In some embodiments, the force is gravity. In such embodiments, the method includes rotating the first material layer, second material components, and carrier. In other embodiments, the process includes positioning the second material components below (with respect to gravity) the carrier and applying a vacuum (e.g., using the vacuum channels described above with respect to arrangement 202) to hold the components in place until the first material layer is applied (this may be particularly advantageous in packaging environments that are not otherwise in vacuum). When the second material components are then positioned on the first material layer, the vacuum is released, and the second material components move toward the first material by gravity. Then, the first material layer and second material components are bonded. In some embodiments, a different force is used. For example, springs (or similar force) may be applied in the carrier cavities and under the covers, the springs will move the components toward the material layer. Then, the first material layer and second material components are bonded.
In some embodiments, method 100 of
In some embodiments, the first material is glass. In some embodiments, the first material is a borosilicate that contains additional elements to fine tune properties. An example of a borosilicate is by CORNING EAGLE, which produces an alkaline earth boro aluminosilicate (a silicate loaded with boron, aluminum, and various alkaline earth elements). Other variations are available from ASAHI GLASS or SCHOTT.
In some embodiments, method 500 includes bonding with solder preform. In some embodiments, method 500 includes bonding with deposited solder. Method 500 can be used in any bonding technique where an excess of bonding material is used. For example, in electroplating typical thickness of the bonding material is on the order of a few microns, while the actual amount at the bonding interface can be much less. Method 500 may be particularly advantageous where the bonding material is in liquid state, at some point during the bonding process. In embodiments where the bonding material is solder preform, method 500 can further include positioning a solder preform over the grooves in the first portion, heating the solder preform, and cooling the solder preform so that the first and second portions bond. In some embodiments, step 510 (the first and second portions are bonded at the bond region) includes heating a material (e.g., solder preform, deposited solder) and allowing it to cool (e.g., passive cooling where heat is allowed to dissipate to the local environment, active cooling where, for example, air is forced over the device, etc.).
As used herein, a “groove” can be understood to include a topography below a surface in a bond region. For example, in the bond region 604 of device 600, grooves 610 are created below the bond surface of substrate 602. In some embodiments, grooves are created by removing volume from a surface of a substrate (e.g., by etching the substrate, as discussed further herein). In some embodiments, grooves are created by selectively raising the surface (e.g., by a deposition, growth (e.g., with silicide)) of the substrate in the bond region but not raising all the surface in the region. Device 600 depicts eight grooves, but it will be readily appreciated that different numbers of grooves can be used (see, e.g.,
Returning to
In some embodiments, the grooves do not form an acute angle with the surface. In
In some embodiments, the depth of the groove is determined by the width of the groove; a desired depth can be achieved by selecting the width of the grooves in combination with a known angle of the sidewalls. For a given depth “D” and angle α, the width “W” of the grooves (and, if the grooves are formed by etch, the width of the etch line) can be determined using the equation: D=(W*tan α)/2. A depth (or width) of the groove may be determined through a desired volume of the groove. For example, consider an embodiment where a bonding component (e.g., solder preform 606 in
Method 500 can further include a step of adding a cavity to the first portion of the device, wherein the cavity is deeper than the grooves.
In some embodiments, step 506 (aligning a second portion of the device with the first portion 506) includes aligning mutual bond regions of the first and second portions. In some embodiments, aligning includes aligning the grooves of the first portion with a bonding region of the second portion. In embodiments where a second portion includes a metallizing ring on the second portion, aligning the two portions can include aligning the ring with the grooves. In some embodiments, aligning is performed without reference to the bond regions of the first and second portions.
In some embodiments, step 508 (the first portion and second portion are moved toward each other) includes holding one portion stationary while the other is moved so that the first and second portions are moved toward each other. In some embodiments, both portions are moved simultaneously.
In some embodiments where a depth of a groove is self-limited (e.g., using the crystalline structure to limit depth etch, discussed above), the length of a groove is determined by alignment accuracy. In such embodiments, when a groove is perfectly aligned to the crystal orientation, then the length of the groove is unbounded. In embodiments where the groove is misaligned from the crystal orientation, the groove width broadens corresponding to the (length of the groove) multiplied by (tan(theta)), where theta is the angular difference between the groove and the crystal. Some embodiments may limit the length of the groove to satisfy a desired limit on the broadening of the width of the grooves.
In some embodiments, a width of a groove may be dictated by an amount of preform in need of accommodation. For example, the preform is 25 um thick and 500 um wide, with a cross-sectional area of 1.25e4 um2. In some embodiments, ˜80% of the preform is accommodated, so the grove widths at 35 um (e.g., after etch formation). In some embodiments, the seal ring width is 750 um, so seventeen 35 um grooves can be fitted. In some embodiments, the lengths of the grooves is dictated by the alignment accuracy of the mask with respect to the crystal of a wafer (e.g., Si wafer). In some embodiments, the length is 1 mm. A higher length may be allowed by improve alignment.
Returning to
The plurality of grooves may be of different lengths. In device 700, for example, groove 712 is longer than groove 710. In some embodiments, the plurality of grooves have equal length. Further, the sectioned grooves in
In some embodiments, as illustrated in
Returning to
Turning to
In some embodiments, step 802 includes providing the plurality of components in a layer. In such embodiments, step 810 or step 812 includes positioning the layer on the carrier. In such embodiments, step 814 (singulating the respective pairs of first and second electromechanical components to produce the plurality of MEMS devices) can be used. In some embodiments, the layer is wafer size. Other layer sizes (e.g., panel scale) could be used without deviating from the scope of this disclosure. In some embodiments, the layer is round. Other layer shapes (e.g., square layers) could be used without deviating from the scope of this disclosure. In some embodiments, one or both of the first and second electromechanical components are round. Other component shapes (e.g., square component) could be used without deviating from the scope of this disclosure.
In some embodiments, step 804 includes providing a carrier with a plurality of cavities, each at a respective position of the carrier. In such embodiments, step 810 includes positioning the non-defective second electromechanical components in a respective cavity.
In some embodiments, step 806 includes electrically testing the plurality of electromechanical components. In some further embodiments, step 806 includes at least one of identifying a short circuit, identifying an open circuit, probing voltage ranges, and/or probing resistance value.
In some embodiments, step 806 mechanically testing the plurality of electromechanical components. Mechanical testing could include, for example, identifying a broken hinge, optical profilometry, and resonance frequency measurements. Mechanical testing can be performed using visual inspection tools.
In some embodiments, identifying a defective component (step 806) includes producing a bad device map. In some embodiments, the bad device map includes positions of known good components. In some embodiments, step 806 includes identifying more than one defective component.
In some embodiment, step 810 includes utilizing a pick-and-place machine to position the second electromechanical components. In some embodiments, an additional step removing the carrier is added to method 800.
In some embodiments, the MEMS devices is a bolometer and the first electromechanical components are bolometer covers.
In some embodiments, the first electromechanical components include glass and the second electromechanical components include silicon.
In some embodiments, an electromechanical component includes an electrical component only, a mechanical component only, or both. In some embodiments, an electromechanical component includes a cover.
Method 1000 includes Step 1002, providing a substrate. In some embodiments, the substrate is made of glass. In some embodiments, the substrate is low temperature polycrystalline silicon. In some embodiments, the substrate is a borosilicate that contains additional elements to fine tune properties. An example of a borosilicate is by CORNING EAGLE, which produces an alkaline earth boro aluminosilicate (a silicate loaded with boron, aluminum, and various alkaline earth elements). Other variations are available from ASAHI GLASS or SCHOTT.
In some embodiments, a flat panel glass process is used to manufacture the electromechanical system. In some embodiments, a liquid crystal display (LCD) process is used to manufacture the electromechanical system. In some embodiments, an OLED display process or an x-ray panel process is used. Employing a flat panel glass process may allow for increased substrate sizes, thereby allowing for a higher number of electrochemical systems per substrate, which reduces processing costs. “Panel level” sizes can include 300 mm×400 mm, 360 mm×465 mm, 400 mm×500 mm, 550 mm×650 mm, 620 mm×750 mm, 680 mm×880 mm, 730 mm×920 mm, 1100 mm×1300 mm, 1300 mm×1500 mm, 1500 mm×1850 mm, 1950 mm×2250 mm, 2200 mm×2500 mm, and 2840 mm×3370 mm. Further, thin film transistors (TFTs) in panel level manufacturing can also reduce cost and so, for example, LCD-TFT processes can be beneficial.
Method 1000 includes Step 1004, adding MEMS to the substrate. Although MEMS is used to describe the addition of structures, it should be appreciated that other structures could be added without deviating from the scope of this disclosure. In embodiments using panel level processing, the MEMS structures may be added using an LCD-TFT process.
Step 1004 may be followed by optional Step 1016, sub-plating. Step 1016 may be used when the substrate is larger than the processing equipment used in subsequent steps. For example, if using a panel level process (such as LCD), some embodiments will include (at Step 1004) cutting the panel into wafer sizes to perform further processing (using, for example, CMOS manufacturing equipment). In other embodiments, the same size substrate is used throughout method 1000 (i.e., Step 1016 is not used).
Method 1000 includes Step 1006, releasing the MEMS from the substrate.
Method 1000 includes Step 1008, post-release processing. Such post-release processing may prepare the MEMS structure for further process steps, such as planarization. In wafer-level processing, planarization can include chemical mechanical planarization. In some embodiments, the further process steps include etch back, where a photoresist is spun onto the topography to generate a more planar surface, which is then etched. Higher control of the etch time can yield a smoother surface profile. In some embodiments, the further process steps include “spin on glass,” where glass-loaded organic binder is spun onto the topography and the result is baked to drive off organic solvents, leaving behind a surface that is smoother.
Method 1000 includes Step 1010, vacuum encapsulation of the MEMS structure, where necessary. Vacuum encapsulation may be beneficial to prolong device life.
Method 1000 includes Step 1012, singulation. Some embodiments may include calibration and chip programming, which may take into account the properties of the sensors. Methods described herein may be advantageous in glass substrate manufacturing processes because uniformity in glass lithography capabilities is limited. As a further advantage, glass has a lower thermal conductivity and so a glass substrate can be a better thermal insulator; by manufacturing thin structures separating a bolometer pixel from a glass substrate, embodiments herein may better serve to thermally isolate the glass bolometer pixel from the packaging environment.
Method 1000 includes Step 1014, attachment of a readout integrated circuit (ROIC) and flex/PCB attachment. Processes and devices described herein may have the further advantage that the area required for signal processing can be much smaller than the sensing area which is dictated by the sensing physics. Typically, sensors are integrated on top of CMOS circuitry, and area driven costs lead to a technology node that is not optimal for the signal processing task. Processes described herein can use a more suitable CMOS and drive down the area required for signal processing, freeing the sensor from any area constraints by leveraging the low cost of FPD (flat panel display) manufacturing. In some embodiments, the ROIC is specifically designed to meet requirements for sensing a specific electromagnetic wavelength (such as X-Rays, THz, LWIR).
In some embodiments, a sensor includes a glass substrate, a structure manufactured from any of the methods described herein and coupled to the glass substrate, and a sensor pixel coupled to the structure. By way of examples, sensors can include resistive sensors and capacitive sensors.
In some embodiments, the MEMS devices manufactured by processes herein are bolometers, each including a glass substrate and a bolometer pixel coupled to the structure. In some embodiments, a bolometer includes a MEMS or NEMS device manufactured by an LCD-TFT manufacturing process.
Bolometers can be used in a variety of applications. For example, long wave infra-red (LWIR, wavelength of approximately 8-14 μm) bolometers can be used in the automotive and commercial security industries. For example, LWIR bolometers with QVGA, VGA, and other resolution. Terahertz (THz, wavelength of approximately 0.1 to 1.0 mm) bolometers can be used in security (e.g., airport passenger security screening) and medical (medical imaging). For example, THz bolometers can have the QVGA resolution (320×240) or other resolutions. Some electrochemical systems can include X-Ray sensors or camera systems. Similarly, LWIR and THz sensors are used in camera systems. Some electromechanical systems are applied in medical imaging, such as endoscopes and exoscopes.
Other electromechanical systems include scanners for light detection and ranging (LIDAR) systems. For example, optical scanners where spatial properties of a laser beam could be shaped (for, e.g., beam pointing). Electromechanical systems include inertial sensors (e.g., where the input stimulus is linear or angular motion). Some systems may be used in bio sensing and bio therapeutic platforms (e.g., where biochemical agents are detected).
As used herein, the term “MEMS” can be understood to include electromechanical systems having feature sizes of approximately 1 mm and below. For example, the term “MEMS” can be understood to include nano electromechanical systems (“NEMS”).
In a first embodiment, a method of manufacturing a plurality of MEMS devices, each device comprising a first material and a second material with different coefficients of thermal expansion (CTE), the method comprises: providing a carrier with substantially equal CTE as the first material, the carrier comprising a plurality of cavities; positioning a plurality of components in respective cavities of the carrier, the components comprising the second material; positioning a layer of the first material on the second material components; bonding the first material layer and the second material components; removing the carrier; and singulating the first material layer to produce the plurality of MEMS devices.
In second embodiment, the method of embodiment 1, wherein providing the carrier comprises providing a carrier layer of the first material.
In a third embodiment, the method of embodiment 1, wherein providing the carrier comprises providing at least one of a ceramic material or a metal.
In a fourth embodiment, the method of any of embodiments 1-3, wherein providing the carrier comprises: providing a first carrier layer; providing a second carrier layer; bonding the first and second carrier layers; removing material from one or both of the first and second carrier layers to create the plurality of cavities.
In a fifth embodiment, the method of any of embodiments 1-4, further comprising applying a vacuum, and wherein bonding the first material layer and second material components is performed while applying the vacuum.
In a sixth embodiment, the method of embodiment 5, wherein providing the carrier comprises providing a carrier with a vacuum channel in each cavity.
In a seventh embodiment, the method of any of embodiments 1-6, wherein providing the carrier comprises providing a round wafer.
In an eighth embodiment, the method of any of embodiments 1-6, wherein providing the carrier comprises providing a square wafer.
In a ninth embodiment, the method of any of embodiments 1-8, wherein providing the carrier comprises providing a 6-inch wafer.
In a tenth embodiment, the method of any of embodiments 1-8, wherein providing the carrier comprises providing an 8-inch wafer.
In an eleventh embodiment, the method of any of embodiments 1-6, wherein providing the carrier comprises providing a panel.
In a twelfth embodiment, the method of any of embodiments 1-11, wherein positioning the plurality of components comprises applying a vacuum to the components to secure the components to the carrier.
In a thirteenth embodiment, the method of embodiment 12, wherein providing the carrier comprises providing a carrier with a vacuum channel in each cavity, and wherein applying a vacuum comprises applying a vacuum to the components through the channel.
In a fourteenth embodiment, the method of any of embodiments 1-13, wherein each of the plurality of MEMS devices comprises a cover of the second material.
In a fifteenth embodiment, the method of any of embodiments 1-14, wherein each component comprises side walls with a metalized surface.
In a sixteenth embodiment, the method of embodiment 15, wherein each component's sidewalls define a cavity in the respective component.
In a seventeenth embodiment, the method of embodiment 16, further comprising creating the cavity in the respective component before positioning the components in the carrier.
In an eighteenth embodiment, the method of embodiment 16, further comprising creating the cavity in the respective component after positioning the components in the carrier.
In a nineteenth embodiment, the method of any of embodiments 15-18, further comprising creating the metalized surface before positioning the components in the carrier.
In a twentieth embodiment, the method of any of embodiments 15-18, further comprising creating the metalized surface after positioning the components in the carrier.
In a twenty first embodiment, the method of any of embodiments 15-20, wherein bonding the first material layer and the second material components comprises depositing bonding components on the metalized surfaces.
In a twenty second embodiment, the method of embodiment 21, wherein the bonding components comprise solder preforms, deposited solder, or both.
In a twenty third embodiment, the method of any of embodiments 1-22, wherein bonding the first material layer and the second material components comprises growing bonding components by deposition.
In a twenty fourth embodiment, the method of any of embodiments 1-23, wherein bonding the first material and second material comprises applying a temperature less than 350 C.
In a twenty fifth embodiment, the method of any of embodiments 1-24, wherein bonding the first material and second material comprises applying a temperature of approximately 300 C.
In a twenty sixth embodiment, the method of any of embodiments 1-25, further comprising rotating the first material layer, second material components, and carrier, after positioning the first material layer on the second material components and before bonding the first material layer and second material components.
In a twenty seventh embodiment, the method of any of embodiments 1-26, wherein singulating comprises dicing the first material layer using a dicing saw.
In a twenty eighth embodiment, the method of any of embodiments 1-26, wherein singulating comprises dicing the first material layer using a scribe and break process.
In a twenty ninth embodiment, the method of any of embodiments 1-28, wherein the first material and second material are selected from glass and silicon.
In a thirtieth embodiment, a MEMS device comprises: a first portion; and a second portion bonded to the first portion at a bond region, the bond region comprising a plurality of grooves.
In a thirty first embodiment, the MEMS device of embodiment 30, wherein the grooves comprise a V-shape.
In a thirty second embodiment, the MEMS device of any of embodiments 30-31, wherein the grooves are formed in a surface of the first portion and each groove comprises two side walls at about 54 degrees to the surface.
In a thirty third embodiment, the MEMS device of embodiment 30, wherein the grooves do not form an acute angle with the surface of the second portion.
In a thirty fourth embodiment, the MEMS device of any of embodiments 30-33, wherein the first portion comprises the grooves and a cavity deeper than the grooves.
In a thirty fifth embodiment, the MEMS device of embodiment 34, wherein the MEMS device comprises a bolometer and the cavity encloses a light sensor.
In a thirty sixth embodiment, the MEMS device of any of embodiments 30-35, wherein the plurality of grooves comprises multiple sectioned grooves arranged end-to-end.
In a thirty seventh embodiment, the MEMS device of any of embodiments 30-36, further comprising solder in the grooves and between the first and second portions.
In a thirty eighth embodiment, the MEMS device of embodiment 37, wherein the solder preform has a first volume, wherein the plurality of grooves define a second volume in the first portion, and wherein the second volume is greater than or equal to the first volume.
In a thirty ninth embodiment, the MEMS device of any of embodiments 30-38, further comprising an adhesive layer in the grooves and between the first and second portions.
In a fortieth embodiment, the MEMS device of any of embodiments 30-39, wherein the grooves are formed in a surface of the first portion and wherein the device further comprises a metalizing ring attached to the second portion.
In a forty first embodiment, a method of manufacturing a MEMS device, the device comprising a bond region, the method comprises: providing a first portion of the device; adding a plurality of grooves to the first portion at the bond region; positioning solder (e.g., solder preform, deposited solder) over the grooves; aligning a second portion of the device with the first portion; heating the solder; moving the first portion toward the second portion; and cooling the solder so that the first portion bonds to the second portion at the bond region.
In a forty second embodiment, the method of embodiment 41, wherein the grooves comprise side walls at about 54 degrees to a surface of the first portion.
In a forty third embodiment, the method of any of embodiments 41-42, wherein the solder has a first volume and the plurality of grooves define a second volume in the first portion, and wherein the second volume is greater than or equal to the first volume.
In a forty fourth embodiment, the method of any of embodiments 41-43, wherein the plurality of grooves comprises multiple sectioned grooves arranged end-to-end.
In a forty fifth embodiment, the method of any of embodiments 41-44, further comprising adding a metalizing ring to the second portion of the device.
In a forty sixth embodiment, the method of any of embodiments 41-45, further comprising adding a cavity to the first portion of the device, wherein the cavity is deeper than the grooves.
In a forty seventh embodiment, the method of embodiment 46, wherein the cavity and grooves are added to the first portion in a same etch processing step.
In a forty eighth embodiment, the method of embodiment 46, wherein the cavity and grooves are added to the first portion in different processing steps.
In a forty ninth embodiment, the method of any of embodiments 46-48, wherein the MEMS device comprises bolometers and the cavity encloses a light sensor.
In a fiftieth embodiment, the method of any of embodiments 41-49, further comprising at least one step in any of methods 1-29.
In a fifty first embodiment, a method of manufacturing a plurality of MEMS devices, the method comprising: providing a layer comprising a plurality of first electromechanical components; providing a carrier comprising a plurality of positions, each position associated with a respective one of the plurality of first electromechanical components; identifying a defective component in the plurality of first electromechanical components; positioning a plurality of second electromechanical components at respective positions on the carrier but not a position associated with the defective electromechanical component; positioning the layer on the carrier; bonding respective pairs of first and second electromechanical components; removing the carrier; and singulating the layer to produce the plurality of MEMS devices.
In a fifty second embodiment, the method of embodiment 51, wherein identifying the defective component comprises electrically testing the plurality of first electromechanical components.
In a fifty third embodiment, the method of embodiment 52, wherein identifying the defective component comprises identifying at least one of a short circuit or an open circuit.
In a fifty fourth embodiment, the method of any of embodiments 51-53, wherein identifying the defective component comprises mechanically testing the plurality of first electromechanical components.
In a fifty fifth embodiment, the method of any of embodiments 51-54, wherein identifying the defective component comprises producing a bad device map.
56. In a fifty sixth embodiment, the method of any of embodiments 51-55, wherein identifying the defective component comprises identifying more than one defective component and wherein positioning the plurality of second electromechanical components comprises positioning the plurality of second electromechanical components at respective positions on the carrier but not positions associated with the more than one defective electromechanical component.
In a fifty seventh embodiment, the method of any of embodiments 51-56, wherein the layer is wafer size.
In a fifty eighth embodiment, the method of any of embodiments 51-57, wherein the components are round.
In a fifty ninth embodiment, the method of any of embodiments 51-58, wherein the components comprise a bolometer cover.
In a sixtieth embodiment, the method of any of embodiments 51-59, wherein the components comprise silicon.
In a sixty first embodiment, the method of any embodiments 51-60 wherein the carrier comprises a plurality of cavities, each at a respective position of the carrier.
In a sixty second embodiment, the method of any of embodiments 51-61, further comprising at least one step in any of methods 1-29 and 41-49.
In a sixty third embodiment, a method of manufacturing a MEMS device, the method comprises: providing a transparent cover with a bond region and a cavity; and applying an adhesion layer in the bond region and in the cavity, wherein the adhesion layer is positioned in the cavity to block radiation reaching a reference sensor.
In a sixty fourth embodiment, the method of embodiment 63, further comprising at least one step in any of methods 1-29, 41-49, and 51-61.
In a sixty fifth embodiment, a MEMS device comprises: a substrate with a reference sensor and an active sensor; and a transparent cover comprising a bond region and a cavity, wherein the substrate and the transparent cover are bonded at the bond region using adhesive, and wherein the transparent cover comprises adhesive in the cavity positioned to block radiation reaching the reference sensor.
In a sixty sixth embodiment, the MEMS device of embodiment 65, wherein the cover further comprises a plurality of grooves in the bond region.
In a sixty seventh embodiment, the MEMS device of embodiment 66, wherein the grooves comprise a V shape.
In a sixty eighth embodiment, the MEMS device of any of embodiments 66-67, wherein the grooves are formed in a surface of the transparent cover and each groove comprises two side walls at about 54 degrees to the surface.
In a sixty ninth embodiment, the MEMS device of embodiment 66, wherein the grooves do not form an acute angle with the surface of the transparent cover.
In a seventieth embodiment, the MEMS device of any of embodiments 66-69, wherein the cavity is deeper than the grooves.
In a seventy first embodiment, the MEMS device of any of embodiments 66-70, wherein the plurality of grooves comprises multiple sectioned grooves arranged end-to-end.
In a seventy second embodiment, the MEMS device of any of embodiments 66-71, further comprising solder in the grooves and between the substrate and transparent cover.
In a seventy third embodiment, the MEMS device of embodiment 72, wherein the solder preform has a first volume, wherein the plurality of grooves define a second volume in the transparent cover, and wherein the second volume is greater than or equal to the first volume.
In a seventy fourth embodiment, the MEMS device of any of embodiments 66-73, wherein the grooves are formed in a surface of the transparent cover and wherein the device further comprises a metalizing ring attached to the substrate.
In a seventy fifth embodiment, the MEMS device of any of embodiments 65-74, wherein the MEMS device comprises a bolometer and the cavity encloses a light sensor.
Although the disclosed embodiments have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the disclosed embodiments as defined by the appended claims. For example, although this disclosure is primarily described with respect to glass MEMS plates/panels, one of skill in the art will recognize that other MEMS plates/panels could also be used without deviating from the scope of the disclosure. Such others MEMS plates may include, but are not limited to, organic materials (plastics, polymers) and metals (e.g., stainless steel). As used herein, the terms “plate” and “panel” are synonymous.
The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a”, “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
This application claims benefit of U.S. Provisional Application No. 63/123,932, filed Dec. 10, 2020, the entire disclosure of which is herein incorporated by reference for all purposes.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/062674 | 12/9/2021 | WO |
Number | Date | Country | |
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63123932 | Dec 2020 | US |