Device using ordered semiconductor alloy

Abstract

An ordered-disordered transition is observed in semiconductor alloys which enables either the ordered or disordered structure to be produced.

Description

Order-disorder transitions can be effected as described above in preferred structures comprising at least one strained epitaxial germanium-silicon semiconductor alloy layer.

Claims

1. A semiconductor device comprising a superlattice of interleaved first and second semiconductor layers, such interleaved first and second layers having first and second compositions, said first composition comprising ordered Ge_x Si₁-x.

2. A device as recited in claim 1 further comprising first and second semiconductor layers on opposed major surfaces of said superlattice.

3. A device as recited in claim 1 further comprising electrical contacts to said first and second layers.

4. A device as recited in claim 3 in which said first and second layers have opposite conductivity types.

5. A device as recited in claim 1 further comprising a light source, said source illuminating said superlattice.

6. A device as recited in claim 5 in which the beam from source is parallel to said interleaved layers.

7. A device as recited in claim 5 in which the beam from source is perpendicular to said interleaved layers.

8. A device as recited in claim 7 further comprising means for scanning said light beam on said superlattice.

9. A device as recited in claim 8 further comprising means for detecting light reflected from said superlattice. PAR

10. A device as recited in claim 2 further comprising source and drain electrodes to said interleaved layers.

11. A device as recited in claim 10 further comprising a gate electrode.

12. A device as recited in claim 2 further comprising a substrate, said superlattice and said first and second layers being disposed on said substrate.

A semiconductor device comprising at least one strained epitaxial semiconductor alloy layer having a composition which comprises ordered Ge_x Si₁-x, the atoms of said ordered Ge_x Si₁-x layer being characterized by long-range periodicity of the constituent

species in the lattice. 14. The device of claim 13, said at least one layer being comprised in a superlattice of interleaved first and second semiconductor layers, such interleaved first and second layers having first and second compositions, said first composition comprising ordered Ge_x Si₁-x. 15. The device of claim 14, further comprising first and second semiconductor layers on opposed major surfaces of said superlattice. 16. The device of claim 15, further comprising a substrate, said superlattice and said first and second layers being disposed on said substrate. 17. The device of claim 14, said first and second layers having opposite conductivity types. 18. The device of claim 13, further comprising an electrical contact to said layer. 19. The device of claim 18, comprising a plurality of electrical contacts to said layer, said plurality comprising a source contact and a drain contact. 20. The device of claim 19, said plurality comprising a gate contact. 21. The device of claim 13, further comprising a light source for illuminating said layer. 22. The device of claim 21, said light source being adapted for illumination in a direction parallel to said layer. 23. The device of claim 21, said light source being adapted for illumination in a direction perpendicular to said layer. 24. The device of claim 21, further comprising means for scanning light from said source across said layer. 25. The device of claim 24, further comprising means for detecting light reflected from said layer.