Claims
- 1. A semiconductor-on-insulator substrate, comprising:
- a single crystal substrate of sapphire having upper and lower major substrate surfaces; and
- a single crystal layer of a group III-V compound semiconductor material having upper and lower major crystal layer surfaces, said lower major crystal layer surface of said single crystal layer formed on said upper major substrate surface of said single crystal substrate;
- said single crystal substrate including a transition zone adjacent to said upper major substrate surface which contacts said single crystal layer, said transition zone having a lower boundary and an upper boundary that is substantially coincident to said upper major substrate surface of said single crystal substrate, wherein said transition zone has a crystal structure in conformity with that of said single crystal layer at said upper boundary and in conformity with that of said single crystal substrate at said lower boundary, said crystal structure changing gradually from said upper boundary to said lower boundary.
- 2. The semiconductor-on-insulator substrate as claimed in claim 1, wherein said transition zone includes less than five atomic layers.
- 3. The semiconductor-on-insulator substrate as claimed in claim 1, wherein said single crystal layer has a thickness not greater than 2 .mu.m.
- 4. The semiconductor-on-insulator substrate as claimed in claim 1, wherein said single crystal layer comprises two distinct parts different from each other in composition.
- 5. A semiconductor-on-insulator substrate comprising:
- a single crystal substrate of an insulating material and having a first principal surface;
- a single crystal layer structure of group III-V compound semiconductor materials having a second principal surface, said second principal surface formed on said first principal surface; and
- said single crystal substrate having a transition zone adjacent to said first principal surface, said transition zone having an upper boundary substantially coincident with said first principal surface and a lower boundary, wherein said transition zone has a crystal structure at said upper boundary conforming with a crystal structure of said single crystal layer structure at said second principal surface, said crystal structure of said transition zone at said lower boundary conforming with a crystal structure of said single crystal substrate adjacent to said lower boundary.
- 6. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said single crystal substrate comprises sapphire.
- 7. The semiconductor-on-insulator substrate as claimed in claim 6, wherein said single crystal layer structure includes a region formed of InP, said region having a principal surface coincident to said second principal surface.
- 8. The semiconductor-on-insulator substrate as claimed in claim 6, wherein said single crystal layer structure includes a region formed of GaAs, said region having a principal surface coincident to said second principal surface.
- 9. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said single crystal layer structure comprises:
- a first region of GaAs having a principal surface coincident to said second principal surface;
- a second region of an insulating material formed adjacent to said first region and having a principal surface coincident to said second principal surface; and
- a third region of InP formed adjacent to said second region and having a principal surface coincident to said second principal surface.
- 10. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said single crystal layer structure comprises:
- an undoped GaAs layer including said second principal surface;
- an n-type AlGaAs layer formed on said undoped GaAs layer; and
- an n-type GaAs layer formed on said n-type AlGaAs layer.
- 11. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said single crystal layer structure comprises:
- an undoped GaAs layer including said second principal surface;
- an undoped AlGaAs layer formed on said undoped GaAs layer;
- an n-type AlGaAs layer formed on said undoped AlGaAs layer; and
- an n-type GaAs layer formed on said n-type AlGaAs layer.
- 12. The semiconductor-on-insulator substrate as claimed in claim 11, wherein:
- said n-type AlGaAs layer has a composition of Al.sub.0.3 Ga.sub.0.7 As and doped with a concentration of Si of 2.times.10.sup.18 cm.sup.-3 ; and
- said undoped AlGaAs layer has a composition of Al.sub.0.3 Ga.sub.0.7 As.
- 13. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said single crystal layer structure comprises:
- an undoped InGaAs layer including said second principal surface;
- an undoped InAlAs layer formed on said undoped InGaAs layer;
- an n-type InAlAs layer formed on said undoped InAlAs layer; and
- an n-type InGaAs layer formed on said n-type InAlAs layer.
- 14. The semiconductor-on-insulator substrate as claimed in claim 13, wherein:
- said n-type InGaAs layer has a composition of In.sub.0.53 Ga.sub.0.47 As and doped with a concentration of Si of 2.times.10.sup.18 cm.sup.-3 ;
- said n-type InAlAs layer has a composition of In.sub.0.53 Al.sub.0.47 As and doped with a concentration of Si of 2.times.10.sup.18 cm.sup.-3 ;
- said undoped InAlAs layer has a composition of In.sub.0.53 Al.sub.0.47 As; and
- said undoped InGaAs layer has a composition of In.sub.0.53 Ga.sub.0.47 As.
- 15. The semiconductor-on-insulator substrate as claimed in claim 5, wherein said second principal surface is a (100) oriented surface.
- 16. The semiconductor-on-insulator substrate as claimed in claim 15, wherein said first principal surface is an R-surface.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-032016 |
Feb 1992 |
JPX |
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Parent Case Info
This application is a division of application Ser. No. 08/019,888, filed Feb. 19, 1993, now U.S. Pat. No. 5,413,951.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2-94415 |
Apr 1990 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Kasai et al., "Material and device properties of GaAs on sapphire grown by metalorganic chemical vapor deposition" J. Appl. Phys. 60(1), Jul. 1986, pp. 1-5. |
Divisions (1)
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Number |
Date |
Country |
Parent |
19888 |
Feb 1993 |
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