Buried layer in a semiconductor formed by bonding

• US 5,977,604 A
• Filed: 03/08/1996
• Issued: 11/02/1999
• Est. Priority Date: 03/08/1996
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Bowers, John E., Babic, Dubravko Ivan
• Primary Examiner(s): Tran, Minh Loan
• Application Number:
  US08/612,687
• Time in Patent Office: 1,334 Days
• Field of Search: 257/461, 257/466, 257/452, 257/510, 257/513, 257/517, 257/594, 257/618, 257/622, 257/623, 257/624, 257/197, 257/98, 372/45, 372/46
• US Class Current: 257/466
• CPC Class Codes: H01L 29/66234 Bipolar junction transistors [BJT]
• CPC Class Codes: H01L 29/66242 Heterojunction transistors [HBT] with an active layer made of a group 13/15 material H01L29/66318
• CPC Class Codes: H01L 29/66318 Heterojunction transistors
• CPC Class Codes: H01L 31/18 Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
• CPC Class Codes: H01S 5/0207 Substrates having a special shape
• CPC Class Codes: H01S 5/0215 Bonding to the substrate
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/18308 having a special structure for lateral current or light confinement
• CPC Class Codes: H01S 5/18316 Airgap confined
• CPC Class Codes: H01S 5/18341 Intra-cavity contacts
• CPC Class Codes: H01S 5/18369 based on dielectric materials
• CPC Class Codes: H01S 5/1838 Reflector bonded by wafer fusion or by an intermediate compound
• CPC Class Codes: H01S 5/2072 obtained by vacancy induced diffusion

Abstract

Buried layers are formed within a semiconductor. Metallic or insulating buried layers are produced several microns within a semiconductor substrate. The buried layer can confine current to the buried layer itself by using a conductive material to create the buried layer. The buried layer can also confine current to a specified area of the semiconductor, by using an insulating material inside of the buried layer or by leaving a created void within the material. The buried layer is useful in the construction of a semiconductor Vertical Cavity Laser (VCL). A buried isolation layer confines the current to a narrow active region increasing efficiency of the VCL. The buried layer is also useful in fabricating discrete devices, such as diodes, transistors, and photodetectors, as well as fabricating integrated circuits.

Claims

1. A semiconductor optoelectronic device, comprising:

a wafer substrate having a first surface and a second surface;

a first epitaxial mirror having a top surface and a bottom surface, the bottom surface of the first epitaxial mirror coupled to the first surface of the wafer substrate;

a first cladding layer having a first surface and a second surface, the first surface of the first cladding layer coupled to the top surface of the first epitaxial mirror, and the second surface having at least one valley and at least one mesa;

a second cladding layer having a fusion surface and an epitaxial surface, the fusion surface of the second cladding layer coupled to at least one mesa of the second surface of the first cladding layer;

a region having a first surface and a second surface, the first surface of the region coupled to the epitaxial surface of the second cladding layer;

a third cladding layer having a top surface and a bottom surface, the bottom surface of the third cladding layer coupled to the second surface of the region;

a second epitaxial mirror having an epitaxial surface and a contact surface, the epitaxial surface of the second epitaxial mirror coupled to the top surface of the third cladding layer; and

a conductive contact coupled to the contact surface of the second epitaxial mirror.

2. The semiconductor optoelectronic device of claim 1, wherein at least one valley in the first cladding layer contains a conductive material.

3. The semiconductor optoelectronic device of claim 2, wherein the conductive material in the valley does not contact the mesa.

4. The semiconductor optoelectronic device of claim 1, wherein a current source is connected between the conductive material in the valley and the conductive contact.

5. The semiconductor optoelectronic device of claim 1, wherein the fusion surface of the second cladding layer has at least one mesa and at least one valley.

6. The semiconductor optoelectronic device of claim 1, wherein the bottom surface of the third cladding layer has at least one mesa and at least one valley.

7. The semiconductor optoelectronic device of claim 1, wherein the region is an active region.

8. The semiconductor optoelectronic device of claim 1, wherein the region is an absorbing region.

9. The semiconductor optoelectronic device of claim 1, wherein the region is a modulating region.

10. The semiconductor optoelectronic device of claim 1, wherein the semiconductor optoelectronic device is a vertical cavity laser.

11. A transistor comprising:

a first wafer having a first surface and a second surface, the first surface of the first wafer having at least one mesa and at least one valley;

a second wafer having a working surface and a bonding surface, the bonding surface of the second wafer coupled to the first surface of the first wafer and the working surface of the second wafer having at least one mesa and at least one valley; and

a third wafer having a top surface and a bottom surface, the bottom surface coupled to the working surface of the second wafer.

12. A photodetector comprising:

a wafer substrate having a first surface and a second surface, the first surface containing at least one valley and at least one mesa, wherein at least one valley contains a conductive material;

a second wafer having a top surface and a bottom surface, the bottom surface being coupled to the first surface of the first wafer and coupled to the conductive material; and

a conductive contact, coupled to the top surface of the second wafer.

13. The photodetector of claim 12, wherein the conductive material in the valley does not contact the mesa.

14. The photodetector of claim 12, wherein a current source is connected between the conductive material in the valley and the conductive contact.