IPC분류정보
국가/구분 |
United States(US) Patent
등록
|
국제특허분류(IPC7판) |
|
출원번호 |
UP-0804863
(2007-05-21)
|
등록번호 |
US-7659182
(2010-04-02)
|
발명자
/ 주소 |
- Vaganov, Vladimir
- Belov, Nickolai
|
대리인 / 주소 |
Fitch, Even, Tabin & Flannery
|
인용정보 |
피인용 횟수 :
3 인용 특허 :
0 |
초록
▼
Methods of wafer-to-wafer bonding are disclosed. These methods use a force-transposing substrate providing redistribution of the applied force to the local bonding areas across the wafer. Certain versions of the Present Invention also provide a compliant force-distributing member along with applying
Methods of wafer-to-wafer bonding are disclosed. These methods use a force-transposing substrate providing redistribution of the applied force to the local bonding areas across the wafer. Certain versions of the Present Invention also provide a compliant force-distributing member along with applying bonding material to bonding areas in select locations. A predetermined sequence of external force loading and temperature steps ensure creating bonds between the wafers in the bonding areas. The disclosed methods improve wafer bonding, by increasing its uniformity and strength across the wafer, increasing both reproducibility and yield process and decreasing cost of semiconductor and MEMS devices.
대표청구항
▼
We claim: 1. A method of wafer to wafer bonding comprising the steps of: providing at least two wafers to be bonded; providing at least one force-transposing substrate comprising a connecting substrate and transposers having contacting areas and having the thickness larger than the thickness of the
We claim: 1. A method of wafer to wafer bonding comprising the steps of: providing at least two wafers to be bonded; providing at least one force-transposing substrate comprising a connecting substrate and transposers having contacting areas and having the thickness larger than the thickness of the connecting substrate; applying bonding material to at least one of the wafers and creating predetermined bonding areas in selected locations; aligning at least two wafers for bonding and at least one force-transposing substrate; providing a predetermined sequence of the external force loading and temperature steps for creating bonds between the wafers in the bonding areas, wherein the transposers on the force-transposing substrate form an array having layout corresponding to the layout of the bonding areas and the array of transposers redistributes the external force loading to the bonding areas providing uniform and reliable bonding across the wafers. 2. The method of claim 1, wherein the material of the transposers and connecting substrate is chosen from the group of: metal, semiconductor, ceramic, plastic, glass, polymer and combination. 3. The method of claim 1, wherein the force-transposing substrate has two sides, at least one side is profiled and the profiled side is facing one of the bonding wafers. 4. The method of claim 1, wherein the bonding areas have a repeatable pattern with a size and a pitch on the surface of the bonding wafers and at least some of the transposers have the same pitch and the size of contacting areas is selected relative to the size of the corresponding bonding areas. 5. The method of claim 1, wherein the bonding material is chosen from the group of materials consisting of: metal, alloy, solder, fit glass, polymer, adhesive and combination of the above. 6. The method of claim 1, wherein the bonding areas include bonding patterns in the bonding wafers areas not occupied with functional dice, including alignment marks, test structures and periphery of the bonding wafers. 7. The method of claim 1, wherein bonding areas on the surface of bonding wafers are treated before applying the bonding material; said treatment is chosen from the group of processes consisting of: plasma cleaning, plasma etching, plasma activation, chemical cleaning, chemical etching, chemical activation, ultrasonic cleaning, megasonic cleaning, application of adhesion promoter, laser activation, annealing and combination of the above. 8. The method of claim 1, wherein a predetermined sequence of the force loading and temperature steps includes multiple elemental operations chosen from the group of operations consisting of: increasing force, sustaining constant force, decreasing force, increasing temperature, sustaining constant temperature, decreasing temperature and combination of the above. 9. The method of claim 1, further comprising an environment, during the bonding process, characterized by a composition of substances and pressure, wherein said composition of substances is chosen from the group consisting of: gas, liquid, air, nitrogen, inert gas and combination of the above. 10. The method of claim 1, wherein temperature, provided during wafer bonding process, has a predetermined distribution on the surface of the bonding wafers chosen from the group of distributions consisting of: uniform, non-uniform concentric, non-uniform eccentric, with extremum of temperature in the selected areas of the wafer or combination. 11. The method of claim 1, wherein at least one of the bonding wafers is a force-transposing substrate. 12. A method of wafer to wafer bonding comprising the steps of: providing at least two wafers to be bonded; providing at least one force-transposing substrate comprising connecting substrate and transposers having contacting areas; providing at least one compliant force-distributing member; applying bonding material to at least one of the wafers and creating predetermined bonding areas in selected locations; aligning at least two wafers for bonding and the at least one force-transposing substrate; applying the at least one compliant force-distributing member to the at least one force-transposing substrate; providing a predetermined sequence of external force loading and temperature steps for creating bonds between the wafers in the predetermined bonding areas, wherein the compliant force-distributing member redistributes its material across a surface of the force-transposing substrate in the direction of stress gradient, when external force loading is applied, providing distribution of pressure on the surface of the force-transposing substrate and therefore on the predetermined bonding areas. 13. The method of claim 12, wherein the material of compliant force-distributing member is chosen from the group of: graphite, glass fiber, plastic, polymer, polyimide, rubber, silicone, sand, powder, metal, soft alloy, liquid, and combination of the above. 14. The method of claim 12, wherein the compliant force-distributing member is chosen from the group of: one-layer sheet, multi-layered sheet, fabric, flat foil, perforated foil, profiled foil, tape, perforated tape, profiled tape, bag, pillow, mat and combination of the above. 15. The method of claim 12, wherein the force-distributing member provides uniform pressure distribution on the surface of the force-transposing substrate. 16. The method of claim 12, wherein the bonding areas have a repeatable pattern with a size and a pitch on the surface of the bonding wafers and at least some of the transposers have the same pitch and the size of contacting areas is selected relative to the size of the corresponding bonding areas. 17. The method of claim 12, further comprising: positioning the at least one compliant-distribution member relative to a non-bonding surface of a first wafer of the at least two wafers such that the at least one compliant-distribution member is separated from a second wafer of the at least two wafers to be bonded with the first wafer by at least the first wafer and wherein the at least one compliant-distribution member is not bonded with the first wafer or second wafer. 18. The method of claim 12, wherein the bonding material is chosen from the group of materials consisting of: metal, alloy, solder, fit glass, polymer, adhesive and combination of the above. 19. The method of claim 12, wherein the bonding areas include bonding patterns in the bonding wafers areas not occupied with functional dice, including alignment marks, test structures and periphery of the bonding wafers. 20. The method of claim 12, wherein a predetermined sequence of the force loading and temperature steps includes multiple elemental operations chosen from the group of operations consisting of: increasing force, sustaining constant force, decreasing force, increasing temperature, sustaining constant temperature, decreasing temperature and combination of the above. 21. A method of wafer to wafer bonding comprising the steps of: providing at least two wafers to be bonded; providing at least one force-transposing and distributing member comprising a connecting member, made from compliant material, and transposers having contacting areas and containing stiffeners embedded within the compliant material; the connecting member holds all the transposers; applying bonding material to at least one of the wafers and creating predetermined bonding areas in selected locations; aligning at least two wafers for bonding and at least one force-transposing and distributing member; providing a predetermined sequence of the force loading and temperature steps for creating bonds between the wafers in the bonding areas, wherein the compliant connecting member redistributes its material across the surface of transposers in the direction of stress gradient, when external force loading is applied, providing uniform distribution of pressure on the surface of transposers, which form an array having layout corresponding to the layout of the bonding areas, and the force-transposing and distributing member uniformly redistributes external force loading to the bonding areas providing reliable bonding across the wafers. 22. The method of claim 21, wherein the material of compliant connecting member is chosen from the group of: graphite, glass fiber, plastic, polymer, polyimide, rubber, silicone, sand, powder, metal, soft alloy, liquid, and combination of the above. 23. The method of claim 21, wherein the connecting member is chosen from the group of: one-layer sheet, multi-layered sheet, fabric, flat foil, perforated foil, profiled foil, tape, perforated tape, profiled tape, bag, pillow, mat and combination of the above. 24. The method of claim 21, wherein the material of the stiffeners within transposers is chosen from the group of: metal, semiconductor, ceramic, plastic, glass, polymer and combination of the above. 25. The method of claim 21, wherein the shape of the stiffeners within transposers is chosen from the group of: sphere, cylinder, cone, pyramid, parallelepiped, plate, ellipsoid, washer, tore and combination of the above. 26. The method of claim 21, wherein the bonding material is chosen from the group of materials consisting of: metal, alloy, solder, fit glass, polymer, adhesive and combination of the above. 27. The method of claim 21, wherein the bonding areas are created with a process chosen from the group of processes consisting of: photolithography, screen printing, contact printing, spraying with a shadow mask, etching of the deposited material through a shadow mask, laser assisted deposition, dispensing, laser-assisted patterning, e-beam patterning and combination of the above. 28. The method of claim 21, wherein the bonding areas include bonding patterns in the bonding areas not occupied with functional dice, including alignment marks, test structures and periphery of the bonding wafers. 29. The method of claim 21, further comprising: positioning the at least one force-transposing and distributing member relative to a first wafer of the at least two wafers such that the at least one force-transposing and distributing member is separated from a second wafer of the at least two wafers by at least the first wafer and wherein the at least one force-transposing and distributing member is not bonded with the at least two wafers. 30. A method of wafer to wafer bonding comprising the steps of: providing at least two wafers to be bonded; providing at least one compliant force-distributing member; applying bonding material to at least one of the wafers and creating bonding areas; aligning at least two wafers for bonding; applying at least one compliant force-distributing member to at least one wafer for bonding where the compliant force-distribution member is not bonded with any of the at least two wafers; providing a predetermined sequence of the force loading and temperature steps resulting in creating bonds between the wafers in the bonding areas, wherein the compliant force-distributing member redistributes its material across the surface of the bonding wafer in the direction of stress gradient, when external force loading is applied, providing uniform distribution of pressure across the surface of the bonding wafers. 31. The method of claim 30, wherein the material of compliant force-distributing member is chosen from the group of: graphite, glass fiber, plastic, polymer, polyimide, rubber, silicone, sand, powder, soft metal, soft alloy, liquid, and combination of the above. 32. The method of claim 30, wherein the compliant force-distributing member is chosen from the group of: one-layer sheet, multi-layered sheet, fabric, flat foil, perforated foil, profiled foil, tape, perforated tape, profiled tape, bag, pillow, mat and combination of the above. 33. The method of claim 30, wherein the force-distributing member provides uniform pressure distribution on the surface of the bonding wafer.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.