Field effect transistor having source and/or drain forming schottky or schottky-like contact with strained semiconductor substrate
The present invention is a field effect transistor having a strained semiconductor substrate and Schottky-barrier source and drain electrodes, and a method for making the transistor. The bulk charge carrier transport characteristic of the Schottky barrier field effect transistor minimizes carrier surface scattering, which enables the strained substrate to provide improved power and speed performance characteristics in this device, as compared to conventional devices.
1. A device for regulating the flow of electric current, the device comprising:
a silicon channel, wherein the silicon channel is formed over a buried silicon-germanium material under the silicon channel;
a gate electrode on the silicon channel; and
a source electrode and a drain electrode in contact with the silicon channel, wherein at least one of the source electrode and the drain electrode forms a Schottky or Schottky-like contact with the silicon channel.
2. The device of claim 1 , wherein the source electrode and the drain electrode are formed from a member of the group consisting of: Platinum Silicide, Palladium Silicide, and Iridium Silicide.
3. The device of claim 1 , wherein the source electrode and the drain electrode are formed from a member of the group consisting of the rare-earth silicides.
4. The device of claim 1 , wherein a length of the silicon channel is less than or equal to about 100 nm, wherein the silicon channel has channel dopants and further has a channel dopant concentration profile, and wherein the channel dopant concentration varies significantly in the vertical direction and is generally constant in the lateral direction.
5. The device of claim 1 , wherein the silicon channel has channel dopants and further has a channel dopant concentration profile, and wherein the channel dopant concentration varies significantly in the vertical and lateral directions.
6. The device of claim 5 , wherein the channel dopants are selected from the group consisting of: Arsenic, Phosphorous, and Antimony.
7. The device of claim 5 , wherein the channel dopants are selected from the group consisting of: Boron, Indium, and Gallium.
8. The device of claim 1 , wherein a length of the silicon channel is less than or equal to about 100 nm.
9. The device of claim 1 , wherein the gate electrode comprises:
a gate insulator including an electrically insulating layer disposed on the silicon channel; and
a conducting film on the insulating layer.
10. The device of claim 9 , wherein the gate electrode further comprises a gate sidewall spacer comprising at least one sidewall insulating layer on at least one sidewall of the gate electrode.
11. The device of claim 9 , wherein the gate insulator has a dielectric constant greater than 4.0.
12. The device of claim 9 , wherein a length of the silicon channel is less than or equal to about 100 nm, wherein the silicon channel has channel dopants and further has a channel dopant concentration profile, and wherein the channel dopant concentration varies significantly in the vertical direction and is generally constant in the lateral direction.
13. The device of claim 9 , wherein the silicon channel has channel dopants and a channel dopant concentration profile, and wherein the channel dopant concentration varies significantly in the vertical and lateral direction.
14. The device of claim 9 , wherein the buried silicon-germanium material under the silicon channel is formed on a SOI substrate.
15. The device of claim 9 , wherein the gate insulator is formed from a member of the group consisting of metal oxides.
16. The device of claim 9 , wherein the conducting film is formed from a member of the group consisting of metals.
17. The device of claim 1 wherein the device is a MOSFET.
18. A device for regulating the flow of electric current, the device comprising:
a silicon channel;
a gate electrode on the silicon channel;
a source electrode and a drain electrode in contact with the silicon channel, wherein at least one of the source electrode and the drain electrode forms a Schottky or Schottky-like contact with the silicon channel, and
silicon-germanium means for straining the silicon channel.
19. The device of claim 18 , wherein the source electrode and the drain electrode are formed from a member of the group consisting of: Platinum Silicide, Palladium Silicide, and Iridium Silicide.
20. The device of claim 18 , wherein the source electrode and the drain electrode are formed from a member of the group consisting of the rare-earth silicides.