SEMICONDUCTOR DEVICES GROWN ON INDIUM-CONTAINING SUBSTRATES UTILIZING INDIUM DEPLETION MECHANISMS

• US 20120037957A1
• Filed: 04/30/2010
• Published: 02/16/2012
• Est. Priority Date: 05/05/2009
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Miller, Thomas J., Haase, Michael A., Sun, Xiaoguang
• Granted Patent: US 8,994,071 B2
• Time in Patent Office: Days
• US Class Current: 257/191
• CPC Class Codes: H01L 21/02392 Phosphides
• CPC Class Codes: H01L 21/02463 Arsenides
• CPC Class Codes: H01L 21/02466 Antimonides
• CPC Class Codes: H01L 21/02469 Group 12/16 materials
• CPC Class Codes: H01L 21/0256 Selenides
• CPC Class Codes: H01L 21/02568 Chalcogenide semiconducting materials not being oxides, e.g. ternary compounds
• CPC Class Codes: H01L 21/02576 N-type
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation
• CPC Class Codes: H01L 33/0087 with a substrate not being a II-VI compound
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/28 containing only elements of Group II and Group VI of the Periodic Table
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

We have observed anomalous behavior of II-VI semiconductor devices grown on certain semiconductor substrates, and have determined that the anomalous behavior is likely the result of indium atoms from the substrate migrating into the II-V layers during growth. The indium can thus become an unintended dopant in one or more of the II-VI layers grown on the substrate, particularly layers that are close to the growth substrate, and can detrimentally impact device performance. We describe a variety of semiconductor constructions and techniques effective to deplete the migrating indium within a short distance in the growth layers, or to substantially prevent indium from migrating out of the substrate, or to otherwise substantially isolate functional II-VI layers from the migrating indium, so as to maintain good device performance.

Claims

1. A semiconductor construction, comprising:

a III-V semiconductor substrate that contains indium;

at least first and second II-VI semiconductor layers formed atop the substrate, the first layer being disposed between the second layer and the substrate; and

an interface disposed between the substrate and the first layer;

wherein the substrate and/or the first layer is adapted to limit the migration of indium from the substrate to the second layer.

2. The construction of claim 1, wherein the substrate comprises a base layer of indium phosphide (InP).

3. The construction of claim 2, wherein the substrate further comprises a buffer layer that contains indium (In).

4. The construction of claim 3, wherein the buffer layer comprises of gallium indium arsenide (GaInAs), aluminum indium arsenide (AlInAs), and/or gallium indium aluminum arsenide (GaInAlAs).

5. The construction of claim 1, wherein the first and second layers are included in a II-VI semiconductor layer stack, the layer stack being effective to convert light at a first wavelength λ

₁ to light at a second wavelength λ

₂.

6. The construction of claim 1, wherein the first layer includes a dopant in an amount effective to deplete indium that has migrated from the substrate.

7. The construction of claim 6, wherein the dopant includes chlorine.

8. The construction of claim 7, wherein the chlorine has a doping density of at least 1×

10¹⁶ cm<sup>−

3</sup> in the first layer.

9. The construction of claim 6, wherein the first layer exhibits through its thickness an indium concentration gradient of at least a factor of 10.

10. The construction of claim 6, wherein the first layer exhibits an indium concentration gradient of at least a factor of 10 over a portion of its thickness, the thickness portion being no more than 1 micron.

12. The construction of claim 10, wherein the thickness portion is no more than 0.6 microns.

13. The construction of claim 1, wherein the first layer does not include a dopant effective to deplete migrating indium but has a thickness sufficient to deplete indium migrating from the substrate.

14. The construction of claim 13, wherein the first layer has a thickness of at least 0.5 microns but less than 10 microns.

16. The construction of claim 13, wherein the first layer exhibits an indium concentration gradient of at least a factor of 10 over its thickness.

17. The construction of claim 1, wherein the substrate comprises a base layer and a buffer layer, the buffer layer having a major surface corresponding to the interface, and the buffer layer exhibiting an abrupt depletion of indium in monolayers proximate the major surface.

11. (canceled)

15. (canceled)

18. A semiconductor construction, comprising:

a III-V semiconductor substrate that contains indium; and

a II-VI semiconductor layer formed atop the substrate;

wherein the substrate includes a base layer and a buffer layer formed thereon, the base layer being composed of a first III-V semiconductor material that includes indium as a matrix element, and the buffer layer being composed of a second III-V semiconductor material that does not include indium as a matrix element, such that migration of indium from the base layer to the II-VI layer is substantially avoided.

19. The construction of claim 18, wherein the second III-V semiconductor material is selected from the group of doped or undoped GaAsSb, AlAsSb, and AlGaAsSb.

20. The construction of claim 18, wherein the first III-V semiconductor material is doped or undoped indium phosphide (InP).

21. A semiconductor construction, comprising:

a first II-VI semiconductor layer that contains an indium dopant and another dopant, the another dopant being present in an amount effective to promote depletion of the indium dopant during a growth phase of the first layer; and

a second II-VI semiconductor layer formed atop the first layer;

wherein the second layer contains an average concentration of indium that is less than an average concentration of indium in the first layer.

23. The construction of claim 21, wherein the another dopant comprises an n-type dopant selected from the group of aluminum (Al), chlorine (Cl), gallium (Ga), bromine (Br), and iodine (I).

22. (canceled)

24-27. -27. (canceled)