Optoelectronic device and method of manufacture thereof

Patent metadata

Field	Value
Publication number	US-2022013988-A1
Application number	US-202117364837-A
Country	US
Kind code	A1
Filing date	Jun 30, 2021
Priority date	Jul 6, 2020
Publication date	Jan 13, 2022
Grant date	—

Abstract

A method of fabricating an optoelectronic component, performed on a multi-layered wafer disposed on a substrate. The method comprises the steps of: etching the multi-layered wafer, thereby defining a slab and a multi-layered ridge, the slab having an upper surface below the ridge and being located between the multi-layered ridge and the substrate; selectively epitaxially growing a III-V semiconductor cladding adjacent to a first and second sidewall of the ridge, the cladding layer extending from the upper surface of the slab along the first and second sidewalls, and thereby cladding an optically active waveguide within the multi-layered ridge; and providing a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

First claim

1 . A method of fabricating an optoelectronic component, performed on a multi-layered wafer disposed on a substrate, the method comprising the steps of:
performing one or more etches to the multi-layered wafer, thereby defining a slab and a multi-layered ridge, the slab having an upper surface below the ridge and being located between the multi-layered ridge and the substrate; selectively epitaxially growing a III-V semiconductor cladding adjacent to a first and second sidewall of the ridge, the cladding layer extending from the upper surface of the slab along the first and second sidewalls, and thereby cladding an optically active waveguide within the multi-layered ridge; and providing a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

2 . The method of claim 1 , wherein the III-V semiconductor cladding is undoped.

3 . The method of claim 1 , wherein the III-V semiconductor cladding is doped with iron.

4 . The method of claim 1 , wherein the III-V semiconductor cladding is formed from one of: InP, GaAs, GaSb, or GaP.

5 . The method of claim 1 , wherein the multi-layered wafer includes one or more III-V semiconductor layers.

6 . The method of claim 1 , wherein the optically active waveguide forms a part of one of: a photodiode; an electro-absorption modulator; and a laser.

7 . The method of claim 1 , wherein the cladding extends from the upper surface of the slab along the first and second sidewalls of the ridge to a point equal in height to an upper surface of a doped layer of the multi-layered ridge.

8 . The method of claim 1 , wherein prior to a first etch of the multi-layered wafer, the method includes depositing a first mask over a region of the multi-layered wafer which is to form the multi-layered ridge, and subsequently etching the unmasked region.

9 . The method of claim 8 , wherein the first mask is retained after the etching, and is present during the selective epitaxial growth of the III-V semiconductor cladding layer.

10 . The method of claim 8 , wherein the first mask is formed of silicon dioxide.

11 . The method of claim 8 , wherein the first etch extends only part way into a base layer of the multi-layered wafer which is adjacent to the substrate.

12 .- 16 . (canceled)

17 . An optoelectronic device, comprising:
a multi-layered ridge, containing an optically active waveguide; a slab, located between the multi-layered ridge and a substrate; a III-V semiconductor cladding, located adjacent to a first and second sidewall of the ridge, and extending from the upper surface of the slab along the first and second sidewalls, thereby cladding the optically active waveguide within the multi-layered ridge; and a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

18 . The optoelectronic device of claim 17 , wherein the III-V semiconductor cladding is undoped.

19 . The optoelectronic device of claim 17 , wherein the III-V semiconductor cladding is doped with iron.

20 . The optoelectronic device of claim 17 , wherein the III-V semiconductor cladding is formed from one of: InP and GaAs.

21 . The optoelectronic device of claim 17 , wherein the multi-layered ridge includes one or more III-V semiconductor layers.

22 . The optoelectronic device of claim 17 , wherein the optically active waveguide forms a part of one of: a photodiode; an electro-absorption modulator; and a laser.

23 . The optoelectronic device of claim 17 , wherein the cladding extends from the upper surface of the slab along the first and second sidewalls of the ridge to a point equal in height to an upper surface of a doped layer of the multi-layered ridge.

24 . The optoelectronic device of claim 17 , wherein the first electrical contact includes a metal layer, located on top of the multi-layered ridge, said metal layer being electrically connected to an uppermost layer of the multi-layered ridge, and also electrically connected to a first contact pad located on an upper surface of the cladding.

25 . The optoelectronic device of any of claim 17 , wherein the second electrical contact is provided in a via through the cladding, said second electrical contact being electrically connected to the slab and a second contact pad located on an upper surface of the cladding.

Assignees

• Rockley Photonics Ltd

Inventors

• Yang Hua

Classifications

• H10F77/147

  Shapes of bodies · CPC title

• H10F77/124

  comprising only Group III-V materials, e.g. GaAs · CPC title

• H10F71/127

  The active layers comprising only Group III-V materials, e.g. GaAs or InP · CPC title

• G02F2201/063

  ridge; rib; strip loaded · CPC title

• G02B2006/12097

  Ridge, rib or the like · CPC title