1. A semiconductor structure comprising:
a surface layer comprising strained silicon disposed over a substrate, the surface layer including a first region having a non-zero first thickness and a second region having a second thickness, the first region having a bottom boundary co-planar with a bottom boundary of the second region and the first thickness being less than the second thickness;
a first source and a first drain in the first region, the first source and the first drain including a first type of dopant; and
a second source and a second drain in the second region, the second source and the second drain including a second type of dopant,
wherein the substrate comprises a region under compressive strain sharing an interface with the surface layer, the strained surface layer enhancing mobility of electrons and the compressively strained substrate region enhancing mobility of holes.
2. The structure of claim 1 further comprising:
an underlying relaxed layer.
3. The structure of claim 2, wherein the underlying relaxed layer comprises germanium.
4. The structure of claim 2, wherein the underlying relaxed layer comprises silicon.
5. The structure of claim 1 further comprising:
an insulator layer,
wherein the surface layer is disposed over the insulator layer.
6. The structure of claim 1, wherein the surface layer comprises tensilely strained silicon.
7. The structure of claim 1, wherein the first type of dopant is p-type and the second type of dopant is n-type.
8. The structure of claim 1, wherein the first type of dopant is n-type and the second type of dopant is p-type.
9. The structure of claim 1 further comprising:
a gate disposed above the surface layer, the first thickness being sufficiently small such that application of an operating voltage to the gate modulates movement of a plurality of charge carriers within the compressively strained substrate region and a majority of the carriers populate the compressively strained substrate region.
10. The structure of claim 9 further comprising:
an insulator between the gate and the surface layer.
11. The structure of claim 1, wherein the compressively strained substrate region comprises silicon.
12. The structure of claim 1, wherein the compressively strained substrate region comprises germanium.
13. The structure of claim 1, wherein the first thickness is greater than 7 \u212b.
14. The structure of claim 1, further comprising:
a gate dielectric disposed over a portion of at least the first region of the surface layer.
15. The structure of claim 14, wherein the gate dielectric layer comprises silicon dioxide.
16. The structure of claim 14, wherein the gate dielectric layer is disposed over a portion of the second region of the surface layer.
17. The structure of claim 14, wherein the gate dielectric layer has a thickness of approximately 10\u2013100 \u212b.
18. The structure of claim 17, wherein the first thickness is approximately 7\u201320 \u212b.
19. The structure of claim 18, wherein the first thickness is less than 10 \u212b.
20. The structure of claim 17, wherein the gate dielectric layer has a thickness of approximately 15 \u212b.
21. The structure of claim 20, wherein the first thickness is less than 10\u212b.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A hydrogen supply system for a fuel cell with an integrated manifold block comprising:
a hydrogen supply line, a hydrogen discharge line, and a hydrogen recirculation line formed in a manifold block mounted on the outside of a plurality of stack modules of a fuel cell stack, wherein the components of the hydrogen supply system including components for supplying and discharging hydrogen and components for recirculating hydrogen are integrally mounted in predetermined positions of the hydrogen supply line, the hydrogen discharge line, and the hydrogen recirculation line to modularize the manifold block and the components of the hydrogen supply system.
2. The hydrogen supply system of claim 1, further comprising a hydrogen supply valve mounted at an inlet of the hydrogen supply line formed on an upper surface of the manifold block.
3. The hydrogen supply system of claim 1, further comprising a recirculation blower mounted on the hydrogen recirculation line which is exposed through an upper surface of the manifold block.
4. The hydrogen supply system of claim 1, further comprising an ejector mounted between the hydrogen supply line and the hydrogen recirculation line in the manifold block.
5. The hydrogen supply system of claim 1, wherein the hydrogen recirculation line is connected to the ejector directly.
6. The hydrogen supply system of claim 1, further comprising a pressure relief valve, which is mounted at inlet of the hydrogen supply line formed on an upper surface of the manifold block.
7. The hydrogen supply system of claim 1, further comprising a water trap and a purge valve, which are connected to the hydrogen discharge line and each mounted on a lower surface and a second side of the manifold block.
8. The hydrogen supply system of claim 1, further comprising a controller located near the manifold block to control the operation of the recirculation blower and the water trap and the opening and closing of the valves.