Epitaxial structure for vertically integrated charge transfer gate technology in optoelectronic materials

Patent metadata

Field	Value
Publication number	US-8963274-B2
Application number	US-201313832450-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Mar 15, 2013
Publication date	Feb 24, 2015
Grant date	Feb 24, 2015

Abstract

A low noise infrared photo detector with a vertically integrated field effect transistor (FET) structure is formed without thermal diffusion. The FET structure includes a high sensitivity photo detector layer, a charge well layer, a transfer well layer, a charge transfer gate, and a drain electrode. In an embodiment, the photo detector layer and charge well are InGaAs and the other layers are InP layers.

First claim

The invention claimed is:

1. A vertically integrated epitaxial field effect transistor structure, comprising:
a high sensitivity photo detector layer;
a charge well;
a transfer well;
a charge transfer gate electrode; and
a drain electrode.

2. The photo detector of claim 1 , wherein the photo detector layer and charge well are buried between carrier migration barrier layers.

3. The photo detector of claim 2 , wherein the photo detector layer is InGaAs, or a member of the InAlGaAsP material system traditionally grown on InP substrates.

4. The photo detector of claim 3 , wherein the photo detector layer is InGaAs.

5. The photo detector of claim 2 , wherein the carrier migration barrier layers are selected from the group consisting of InP, InAlAs, and InAlGaAsP layers.

6. The photo detector of claim 5 , wherein the carrier migration barrier layers are InP.

7. The photo detector of claim 2 , wherein the carrier migration barrier layers comprise hetero structure layers in the InAlGaAsP material system with a concentration gradient comprising a stepped or continuous change in concentration across the layers.

8. The photo detector of claim 1 , wherein the charge well is InGaAs or a member of the InAlGaAsP material system traditionally grown on InP substrates.

9. The photo detector of claim 7 , wherein the heterostructure layers comprise binary, ternary or quaternary compositions of the InAlGaAsP material system.

10. The photo detector of claim 1 , wherein the charge transfer gate electrode and drain electrode comprise Ti, Pt, Au, Ni, Cu, or combinations thereof.

11. The photo detector of claim 1 , wherein the photo detector layer is responsive to a signal with a wavelength in the range of 0.4 to 1.7 micrometers.

12. The photo detector of claim 1 , wherein the charge transfer gate electrode is triggered by an external circuit that controls the collection of photo current.

13. A low noise infrared focal plane detector array that includes a plurality of vertically integrated epitaxial field effect transistor structures, wherein each vertically integrated epitaxial field effect transistor structure comprises:
a high sensitivity photo detector layer;
a charge well;
a transfer well;
a charge transfer gate electrode; and
a drain electrode.

14. The detector array of claim 13 , wherein the photo detector layer and charge well are buried between carrier migration barrier layers.

15. The detector array of claim 13 , wherein the photo detector layer is InGaAs or a member of the InAlGaAsP material system traditionally grown on InP substrates.

16. The detector array of claim 13 , wherein the charge well is InGaAs or a member of the InAlGaAsP material system traditionally grown on InP substrates.

17. The detector array of claim 13 , wherein the charge transfer gate electrode and drain electrode comprise Ti, Pt, Au, Ni, Cu, or combinations thereof.

18. A near IR camera system , comprising:
a focal plane detector array that includes a plurality of low noise IR photo detector elements,
wherein each low noise IR photo detector element is formed without thermal diffusion processes and includes a vertically integrated epitaxial field effect transistor structure, the vertically integrated epitaxial field effect transistor structure comprising:
a high sensitivity photo detector layer;
a charge well;
a transfer well;
a charge transfer gate electrode; and
a drain electrode.

19. The near IR camera system of claim 18 , wherein the photo detector layer and charge well are buried between carrier migration barrier layers.

20. A low noise infrared photo detector, formed without thermal diffusion processes, that includes the vertically integrated epitaxial field effect transistor structure of claim 1 .

Assignees

• Sensors Unlimited Inc

Inventors

• Dixon Peter

Classifications

• H10F39/196

  Junction field effect transistor [JFET] image sensors; Static induction transistor [SIT] image sensors · CPC title

• H10F30/287 Primary

  the devices having PN heterojunction gates · CPC title

• H01L31/1127 Primary

  Electricity · mapped topic