Methods of forming a semiconductor device
View Patent ↗A method and structure for a semiconductor device, the device including a handle wafer, a diamond layer formed directly on a front side of the handle wafer, and a thick oxide layer formed directly on a back side of the handle wafer, the oxide of a thickness to counteract tensile stresses of the diamond layer. Nitride layers are formed on the outer surfaces of the diamond layer and thick oxide layer and a polysilicon is formed on outer surfaces of the nitride layers. A device wafer is bonded to the handle wafer to form the semiconductor device.
1. A method of forming a semiconductor device, comprising:
forming an oxide layer on a back side of a handle wafer substrate;
growing a diamond layer on a front side of the handle wafer substrate, the oxide layer comprising a thickness to counteract tensile stresses of the diamond layer; and
bonding the handle wafer to a device wafer to form the semiconductor device;
depositing a nitride layer on the front and back side of the handle wafer; and
depositing a polysilicon on the front and back side of the handle wafer, followed by polishing the front side polysilicon to a thickness less than the back side polysilicon.
2. The method of claim 1 , wherein the device wafer comprises a device substrate and an oxide layer on each of a front and back side of the device wafer substrate.
3. The method of claim 2 , wherein the oxide layers are formed to a thickness of about 625 Å.
4. The method of claim 1 , wherein tensile stresses absent the diamond layer comprise a bow in the handle wafer substrate of up to about 130 microns.
5. The method of claim 1 , wherein forming the oxide layer comprises depositing/growing oxide to a thickness of about 1.5 to about 2.5 μm.
6. The method of claim 1 , wherein growing the diamond layer comprises growing to a thickness of about 1.5 μm or more.
7. The method of claim 1 , wherein depositing the nitride layer comprises depositing to a thickness of about 500 to about 3000 Å.
8. The method of claim 7 , wherein depositing the nitride layer comprises depositing to a thickness of about 1200 Å.
9. The method of claim 1 , wherein depositing the polysilicon comprises depositing to a thickness of about 2000 Å to about 20,000 Å.
10. The method of claim 1 , wherein polishing the front side polysilicon comprises polishing to a thickness of from about 5,000 Å to about 10,000 Å.
11. The method of claim 1 , wherein bonding comprises thermal bonding, the thermal bonding forming an oxide layer on both a device wafer side and handle wafer side of the semiconductor device.
12. The method of claim 11 , further comprising treating the device side to remove the oxide layer and a portion of a device substrate.
13. A method of forming a semiconductor device, comprising:
forming an oxide layer on a back side of a handle wafer substrate;
growing a diamond layer on a front side of the handle wafer substrate, the oxide layer comprising a thickness to counteract tensile stresses of the diamond layer; and
bonding the handle wafer to a device wafer to form the semiconductor device;
wherein forming an oxide layer on the back side of the handle wafer substrate comprises forming an oxide layer on both a front and back side of the handle wafer substrate, and removing the formed oxide layer from the front side of the handle wafer substrate.
14. The method of claim 13 , wherein the device wafer comprises a device substrate and an oxide layer on each of a front and back side of the device wafer substrate.
15. The method of claim 14 , wherein the oxide layers are formed to a thickness of about 625 Å.
16. The method of claim 13 , further comprising depositing a nitride layer on the front and back side of the handle wafer.
17. The method of claim 16 , wherein depositing the nitride layer comprises depositing to a thickness of about 500 to about 3000 Å.
18. The method of claim 17 , wherein depositing the nitride layer comprises depositing to a thickness of about 1200 Å.
19. The method of claim 16 , further comprising depositing a polysilicon on the front and back side of the handle wafer, followed by polishing the front side polysilicon to a thickness less than the back side polysilicon.
20. The method of claim 19 , wherein depositing the polysilicon comprises depositing to a thickness of about 2000 Å to about 20,000 Å.
21. The method of claim 19 , wherein polishing the front side polysilicon comprises polishing to a thickness of from about 5,000 Å to about 10,000 Å.
22. The method of claim 13 , wherein tensile stresses absent the diamond layer comprise a bow in the handle wafer substrate of up to about 130 microns.
23. The method of claim 13 , wherein forming the oxide layer comprises depositing/growing oxide to a thickness of about 1.5 to about 2.5 μm.
24. The method of claim 13 , wherein growing the diamond layer comprises growing to a thickness of about 1.5 μm or more.
25. The method of claim 13 , wherein bonding comprises thermal bonding, the thermal bonding forming an oxide layer on both a device wafer side and handle wafer side of the semiconductor device.
26. The method of claim 25 , further comprising treating the device side to remove the oxide layer and a portion of a device substrate.