Method for treating a substrate and a substrate
A method for treating a compound semiconductor substrate, in which method in vacuum conditions a surface of an In-containing III-As, III-Sb or III-P substrate is cleaned from amorphous native oxides and after that the cleaned substrate is heated to a temperature of about 250-550° C. and oxidized by introducing oxygen gas onto the surface of the substrate. The invention relates also to a compound semiconductor substrate, and the use of the substrate in a structure of a transistor such as MOSFET.
1. A compound semiconductor substrate, wherein the substrate comprises at least
an In-containing III-As, III-Sb or III-P base material having a first side and a second side, and
a crystalline (3×1)-O, c(4×2)-O, (1×2)-O, (2×3)-O, (3×1)-SnO, (3×3)-SnO, or (1×1)-SnO oxide layer being formed on at least a part of the first side of the base material.
2. The substrate according to claim 1 , wherein the oxide layer has been formed by a method for producing a crystalline oxide layer on an In-containing III-As, III-Sb or III-P compound semiconductor substrate, comprising in vacuum conditions
a surface of an In-containing III-As, III-Sb or III-P substrate which is clean from amorphous native oxides is provided,
the clean substrate is heated to a temperature of about 250-550° C. and, while kept at said temperature, oxidized by introducing oxygen gas onto the surface of the substrate.
3. The substrate according to claim 1 , wherein the oxide layer has a c(4×2)-O crystal structure, when the In-containing III-As base material is InAs or InGaAs.
4. The substrate according to claim 1 , wherein the oxide layer has a (1×1)-SnO crystal structure, when the In-containing III-P base material is InP or InGaP.
5. The substrate according to claim 1 , wherein the base material is a layer, which has been applied on the surface of a Si substrate.
6. The substrate according to claim 1 , wherein the thickness of the oxide layer is typically 0.2-1 nm.
7. The substrate according to claim 1 in a structure of a transistor.
8. The substrate according to claim 1 in a structure of an optoelectronic device.
9. A compound semiconductor substrate, wherein the substrate comprises at least
an In-containing III-As, III-Sb or III-P base material having a first side and a second side, and
a crystalline (3×1)-O, c(4×2)-O, (1×2)-O, (2×3)-O, (3×1)-SnO, (3×3)-SnO, or (1×1)-SnO oxide layer being formed on at least a part of the first side of the base material,
wherein the oxide layer has a (3×1)-O crystal structure, when the In-containing III-As or III-Sb base material is InAs, InSb, InGaAs or InGaSb.
10. A compound semiconductor substrate, wherein the substrate comprises at least
an In-containing III-As, III-Sb or III-P base material having a first side and a second side, and
a crystalline (3×1)-O, c(4×2)-O, (1×2)-O, (2×3)-O, (3×1)-SnO, (3×3)-SnO, or (1×1)-SnO oxide layer being formed on at least a part of the first side of the base material,
wherein the oxide layer has a (1×2)-O crystal structure, when the In-containing III-Sb base material is InSb or InGaSb.
11. A compound semiconductor substrate, wherein the substrate comprises at least
an In-containing III-As, III-Sb or III-P base material having a first side and a second side, and
a crystalline (3×1)-O, c(4×2)-O, (1×2)-O, (2×3)-O, (3×1)-SnO, (3×3)-SnO, or (1×1)-SnO oxide layer being formed on at least a part of the first side of the base material,
wherein the base material is InP and the oxide layer has a (2×3)-O crystal structure.
12. A compound semiconductor substrate, wherein the substrate comprises at least
an In-containing III-As, III-Sb or III-P base material having a first side and a second side, and
a crystalline (3×1)-O, c(4×2)-O, (1×2)-O, (2×3)-O, (3×1)-SnO, (3×3)-SnO, or (1×1)-SnO oxide layer being formed on at least a part of the first side of the base material,
wherein the oxide layer has a (3×1)-SnO or (3×3)-SnO crystal structure, when the In-containing III-As base material is InAs, or InGaAs.