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 layer of a thickness to counteract tensile stresses of the diamond layer. Nitride layers are formed on 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:
on a device wafer, depositing a thin nitride layer on an active side of the device wafer between a diamond layer and the device wafer, wherein the thin nitride layer comprises a thickness of about 500 Å to about 3000 Å;
depositing a polysilicon layer on the active side of the device wafer and on an oxide layer on a back side of the device wafer;
planarizing the polysilicon on the active side of the device wafer; and
attaching the planarized side of the device wafer to a handle wafer to form the semiconductor device.
2. The method of claim 1 , wherein the thin nitride layer is deposited to a thickness of about 1000 Å.
3. The method of claim 1 , further comprising:
depositing polysilicon on the handle wafer side of the semiconductor device; and
polishing a device side of the semiconductor device.
4. The method of claim 3 , wherein polishing comprises polishing the device side of the semiconductor device to within about 0.1 to about 100 μm of a diamond-silicon interface of the device wafer.
5. A method of forming a semiconductor device, comprising:
growing a pad oxide on front and back sides of a device wafer;
depositing a thin (first) nitride layer over the front and back side pad oxide layers;
growing a diamond layer on the front side thin nitride layer;
depositing a second nitride layer on the diamond layer and the back side first nitride layer;
etching the back side to substantially remove the first and second nitride layers;
growing a thermal oxide on the etched back side of the device wafer;
depositing a polysilicon layer on the front side of the device wafer and on the thermal oxide on the etched back side of the device wafer;
planarizing the polysilicon on the front side of the device wafer; and
attaching the planarized side of the device wafer to a handle wafer to form the semiconductor device.
6. The method of claim 5 , wherein growing the pad oxide comprises growing to a thickness of about 650 Å.
7. The method of claim 5 , wherein depositing the first nitride layer comprises depositing to a thickness of about 500 Å to about 3000 Å.
8. The method of claim 7 , wherein depositing the first nitride layer comprises depositing to a thickness of about 1200 Å.
9. The method of claim 5 , wherein growing the diamond layer comprises growing to a thickness of about 1.5 μm.
10. The method of claim 5 , wherein depositing the second nitride layer comprises depositing to a thickness of about 500 Å to about 3000 Å.
11. The method of claim 10 , wherein depositing the second nitride layer comprises depositing to a thickness of about 1200 Å.
12. The method of claim 5 , wherein growing a thermal oxide comprises growing to a thickness of about 2 μm.