Method for fabricating high-quality semiconductor light-emitting devices on silicon substrates
One embodiment of the present invention provides a semiconductor light-emitting device which includes: (1) a silicon (Si) substrate; (2) a silver (Ag) transition layer which is formed on a surface of the Si substrate, wherein the Ag transition layer covers the Si substrate surface; and (3) an InGaAlN, ZnMgCdO, or ZnBeCdO-based semiconductor light-emitting structure which is fabricated on the Ag-coated Si substrate. Note that the Ag transition layer prevents the Si substrate surface from forming an amorphous overcoat with reactant gases used for growing the semiconductor light-emitting structure.
1. A semiconductor light-emitting device, comprising:
a Si substrate;
a silver (Ag) transition layer which is formed on a surface of the Si substrate, wherein the Ag transition layer covers the Si substrate surface, wherein the Ag transition-layer thickness is between 2 and 50 angstroms, and wherein the Ag transition layer exhibits similar lattice structure as the Si substrate; and
an InGaAlN, ZnMgCdO, or ZnBeCdO-based semiconductor light-emitting structure which is epitaxially grown on the Ag-coated Si substrate, wherein the InGaAlN, ZnMgCdO, or ZnBeCdO-based semiconductor light-emitting structure is in contact with the Ag transition layer,
whereby the Ag transition layer prevents the Si substrate surface from forming an amorphous overcoat with reactant gases used for growing the semiconductor light-emitting structure.
2. The semiconductor light-emitting device of claim 1 , wherein the Ag transition layer comprises one or more Ag monolayers.
3. The semiconductor light-emitting device of claim 1 , wherein the Ag transition-layer thickness is not less than 5 angstroms and not more than 20 angstroms.
4. The semiconductor light-emitting device of claim 1 , wherein the Ag transition layer is formed on the Si substrate surface by using one of the following techniques:
electron beam evaporation;
chemical vapor deposition;
physical vapor deposition;
sputtering deposition; and
electroplating.
5. The semiconductor light-emitting device of claim 1 , wherein the Si substrate is a (111) Si substrate.
6. The semiconductor light-emitting device of claim 1 , wherein the semiconductor light-emitting structure can include:
a number of In x Ga y Al 1-x-y N (0≦x≦1, 0≦y≦1) layers; or
a number of Zn x Mg y Cd 1-x-y O (0≦x≦1, 0≦y≦1) layers; or
a number of Zn x Be y Cd 1-x-y O (0≦x≦1, 0≦y≦1) layers.
7. The semiconductor light-emitting device of claim 6 , wherein the semiconductor light-emitting structure comprises one of the following structures:
a P—N junction;
a double heterojunction (DH); and
a multi-quantum well (MQW) structure.