Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
194 words
A method of epitaxially growing a monocrystalline layer of a first material from the vapor phase on an oxide free surface of a substrate of a second material oxidizable in air, said method comprising epitaxially growing a layer of said second material on a support of a monocrystalline material having the desired crystalline structure, reducing the thickness of said support to a value sufficiently less than the thickness of the layer of said second material to enable removal by etching of said support from the layer of said second material, introducing said support and attached layer of said second material into a non-oxidizing atmosphere and then, while in said non-oxidizing atmosphere, subjecting said support and attached layer of said second material to the action of an etch for a time sufficient to cause complete removal of said support but insufficient to cause complete etching of the layer of said second material thereby leaving exposed the surface of the layer of said second material previously attached to said support and growing, by epitaxial deposition from the vapor phase, a monocrystalline layer of said first material on the surface of said second material exposed by etching.
Claim 2
Independent Claim
194 words
A method of epitaxially growing a monocrystalline layer of a first material from the vapor phase on an oxide free surface of a substrate of a second material oxidizable in air, said method comprising epitaxially growing a layer of said second material on a support of a monocrystalline material having the desired crystalline structure, reducing the thickness of said support to a value sufficiently less than the thickness of the layer of said second material to enable removal by etching of said support from the layer of said second material, introducing said support and attached layer of said second material into a non-oxidizing atmosphere and then, while in said non-oxidizing atmosphere, subjecting said support and attached layer of said second material to the action of an etch for a time sufficient to cause complete removal of said support but insufficient to cause complete etching of the layer of said second material thereby leaving exposed the surface of the layer of said second material previously attached to said support and growing, by epitaxial deposition from the vapor phase, a monocrystalline layer of said first material on the surface of said second material exposed by etching.
Claim 3
Dependent Claim
18 words
A method as claimed in claim 1, characterized in that etching is carried out with a gaseous etchant.
Claim 4
Dependent Claim
27 words
The method of claim 2 wherein the first material is gallium indium arsenide, the second material is gallium aluminum arsenide and the monocrystalline material is gallium arsenide.
Claim 5
Dependent Claim
29 words
A method as claimed in claim 3 characterized in that before etching the value of the thickness of the support of gallium arsenide is between 5 and 10 microns.
Claim 6
Dependent Claim
27 words
A method as claimed in claim 3, characterized in that the chemical atmosphere contains gaseous hydrogen halide having a partial pressure between 0.5 and 5.10.sup. -2 atmosphere.
Claim 7
Dependent Claim
23 words
A method as claimed in claim 5, characterized in that the temperature at which etching is carried out is between 650° and 750°C.
Claim 8
Dependent Claim
32 words
A method as claimed in claim 3, characterized in that the step of epitaxially growing from the vapour phase of galliumindiumarsenide (Ga,In)As is carried out at a temperature between 650° and 750°C.
Claim 9
Dependent Claim
36 words
A method as claimed in claim 6, characterized in that the temperature at which the chemical etching is carried out and the temperature of the step of epitaxially growing from the vapour phase are the same.