Performance enhanced silicon-on-insulator technology
View Patent ↗The present invention includes a silicon-on-insulator (SOI) wafer that enhances certain performance parameters by increasing silicon device layer and insulator layer thicknesses and increasing silicon handle wafer resistivity. By increasing the silicon device layer thickness, effects of the floating body problem may be significantly reduced. By increasing the insulator layer thickness and the silicon handle wafer resistivity, influences from the silicon handle wafer on devices formed using the silicon device layer may be significantly reduced. As a result, standard tools, methods, and processes may be used.
1. A silicon-on-insulator wafer comprising:
a silicon handle wafer section having a handle wafer section resistivity greater than about 100 ohm•centimeters;
an insulator layer over the handle wafer section having an insulator layer thickness greater than about 500 nanometers; and
a silicon device layer over the insulator layer comprising:
a first isolation area implanted into the silicon device layer over and approximately adjacent to the insulator layer,
a device body of a first field effect transistor (FET) over the first isolation area;
an FET source of the first FET substantially over the first FET device body;
an FET drain of the first FET substantially over the first FET device body; and
at least one isolation sidewall implanted into the silicon device layer down to the first isolation area to isolate the first FET,
wherein the silicon device layer has a silicon device layer thickness greater than about 400 nanometers.
2. The silicon-on-insulator wafer of claim 1 wherein the handle wafer section resistivity is greater than about 500 ohm•centimeters.
3. The silicon-on-insulator wafer of claim 1 wherein the insulator layer thickness is greater than about 700 nanometers.
4. The silicon-on-insulator wafer of claim 1 wherein the silicon device layer thickness is greater than about 500 nanometers.
5. The silicon-on-insulator wafer of claim 1 wherein a device section resistivity is less than about 25 ohm•centimeters.
6. The silicon-on-insulator wafer of claim 1 wherein the handle wafer section resistivity is approximately 1000 ohm•centimeters, a device section resistivity is approximately 10 ohm•centimeters, the insulator layer thickness is approximately 1000 nm, and the silicon device layer thickness is approximately 1000 nm.
7. The silicon-on-insulator wafer of claim 1 wherein the insulator layer comprises Silicon Dioxide.
8. The silicon-on-insulator wafer of claim 1 further comprising a plurality of FET elements.
9. The silicon-on-insulator wafer of claim 8 wherein one of the plurality of FET elements is electrically isolated from another of the plurality of FET elements.
10. The silicon-on-insulator wafer of claim 9 further comprising at least one isolation trench etched into the silicon device layer down to the insulator layer.
11. The silicon-on-insulator wafer of claim 10 wherein the at least one isolation trench is approximately filled with an oxide material.
12. The silicon-on-insulator wafer of claim 9 further comprising at least one isolation sidewall implanted into the silicon device layer down to the insulator layer.
13. The silicon-on-insulator wafer of claim 8 wherein the plurality of FET elements comprises a plurality of metal oxide semiconductor field effect transistor (MOSFET) elements.
14. The silicon-on-insulator wafer of claim 8 wherein a radio frequency power amplifier comprises certain of the plurality of FET elements.
15. The silicon-on-insulator wafer of claim 14 wherein complementary metal oxide semiconductor circuits comprise certain of the plurality of FET elements.
16. The silicon-on-insulator wafer of claim 8 wherein a radio frequency switch comprises certain of the plurality of FET elements.
17. The silicon-on-insulator wafer of claim 16 wherein complementary metal oxide semiconductor circuits comprise certain of the plurality of FET elements.
18. The silicon-on-insulator wafer of claim 16 wherein the certain of the plurality of FET elements are coupled in series.