Bipolar transistor, semiconductor light emitting device and semiconductor device

• US 20030064538A1
• Filed: 10/31/2002
• Published: 04/03/2003
• Est. Priority Date: 09/13/2000
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Fujimoto, Hidetoshi
• Granted Patent: US 6,605,486 B2
• Time in Patent Office: Days
• US Class Current: 438/48
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01S 5/2231 with inner confining structure only between the active layer and the upper electrode
• CPC Class Codes: H01S 5/3211 characterised by special cladding layers, e.g. details on band-discontinuities
• CPC Class Codes: H01S 5/3219 explicitly Al-free cladding layers
• CPC Class Codes: H01S 5/34326 with a well layer based on InGa(Al)P, e.g. red laser

Abstract

In a GaAs type semiconductor device, In_pGa_1−pN (0<p≦1) is used to thereby form heterojunction having a large difference in energy gap, thereby providing a high performance semiconductor device.

Claims

1. A bipolar transistor comprising:

a substrate;

a collector layer with first conductive type formed on said substrate;

a base layer with second conductive type formed on said collector layer and made of a material selected from the group consisting of GaAs, InGaAs, AlGaAs, InAlGaP, InGaAsP, GaSb, GaAsSb, GaNAs, InGaNAs, SiGe, and HgCdTe; and

an emitter layer with first conductive type formed on said base layer and made of In_pGa<sub>1−

p</sub>N (0<

p≦

1), the emitter layer having a larger bandgap than said base layer.

2. A bipolar transistor according to claim 1, wherein said collector layer is made of a material selected from the group consisting of GaAs, InGaAs, AlGaAs, InAlGaP, InGaAsP, GaSb, GaAsSb, GaNAs, InGaNAs, SiGe, HgCdTe, and InGaN.

3. A bipolar transistor according to claim 1, wherein said substrate is a GaAs substrate.

4. A bipolar transistor according to claim 1, wherein said base layer contains a material selected from the group consisting of GaAs, InGaAs and InGaNAs.

5. A bipolar transistor according to claim 1, wherein the crystal structure of said emitter layer is a zincblende structure.

6. A bipolar transistor according to claim 1, wherein said emitter layer has a thickness of 200 nm or more.

7. A bipolar transistor according to claim 1, the bipolar transistor further comprising an emitter contact layer to easily make ohmic contact between said emitter layer and an emitter electrode.

8. A bipolar transistor according to claim 7, wherein the sum of the thicknesses of said emitter layer and said emitter contact layer is 200 nm or more.

9. A bipolar transistor according to claim 8, wherein said emitter contact layer contains In_qGa₁₋

qN (p<

q≦

1).

10. A bipolar transistor according to claim 1, wherein said first conductive type is an n-type and said second conductive type is a p-type.

11. A semiconductor light emitting device comprising:

a first conductive type clad layer;

an active layer formed on said first conductive type clad layer and made of In_bAl_cGa<sub>1−

b−

c</sub>As_dP<sub>1−

d</sub> (0≦

b≦

1, 0≦

c≦

1, 0≦

b+c≦

1 and 0≦

d≦

1), the active layer emitting light by the injection of current; and

a second conductive type clad layer formed on said active layer and made of In_rGa<sub>1−

r</sub>N (0<

r≦

1).

12. A semiconductor light emitting device according to claim 11, wherein said first conductive type clad layer is made of In_sGa₁₋

sN (0<

s≦

1).

13. A semiconductor light emitting device according to claim 11, wherein said active layer is made of InAlGaP.

14. A semiconductor light emitting device according to claim 11, wherein said first conductive type clad layer is formed on a GaAs substrate.

15. A semiconductor light emitting device according to claim 11, wherein said second conductive type clad layer has a film thickness of 100 nm or more.

16. A semiconductor device comprising:

a first semiconductor layer made of In_tGa<sub>1−

t</sub>N (0<

t≦

1); and

a second semiconductor layer which forms heterojunction with said first semiconductor layer, has higher electron affinity than said first semiconductor and contains a material selected from the group consisting of GaAs, InGaAs, AlGaAs, InAlGaP, InGaAsP, GaSb, GaAsSb, GaNAs, InGaNAs, SiGe and HgCdTe.

17. A semiconductor device according to claim 16, wherein said semiconductor device is a field effect transistor, said first semiconductor layer is a supply layer and said second semiconductor layer is a channel layer.

18. A semiconductor device according to claim 17, the semiconductor device being provided with two or more heterojunctions between said first semiconductor layer and said second semiconductor layer.

19. A semiconductor device according to claim 17, wherein said first semiconductor layer is made of In_uGa₁₋

uN (0.4<

u≦

1).

20. A semiconductor device according to claim 17, wherein said second semiconductor layer is made of InGaAs or InGaNAs.