High-frequency optoelectronic detector, system and method

Patent metadata

Field	Value
Publication number	US-9318516-B2
Application number	US-201313933898-A
Country	US
Kind code	B2
Filing date	Jul 2, 2013
Priority date	Jul 2, 2012
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

An optoelectronic device for detecting electromagnetic radiation and including: a body of semiconductor material delimited by a main surface and including a first region and a second region that form a junction; and a recess formed in the body, which extends from the main surface and is delimited at least by a first wall, the first wall being arranged transverse to the main surface. The junction faces the first wall.

First claim

What is claimed is:

1. An optoelectronic device, comprising:
a body of semiconductor material, the body including a first main surface;
a first region formed in the body;
a second region formed within the first region, wherein the first and second regions are of opposite conductivity types to form a junction between the first and second regions and a depletion region at the junction;
a recess extending from the first main surface of the body through the second region and into the first region to intersect the depletion region at a sidewall of the recess;
a top layer formed over the first main surface that includes a portion formed in the recess, the top layer having an index of refraction that is greater than an index of refraction of the body and being operable to expose the intersected depletion region at said sidewall to electromagnetic radiation propagating through the top layer;
wherein the recess includes a first side wall having a first angle relative to the first main surface of the body, said first angle being between, but not equal to either of, zero and ninety degrees.

2. The optoelectronic device of claim 1 , wherein the recess includes a second side wall having a second angle relative to the first main surface of the body, said second angle being between, but not equal to either of, zero and ninety degrees.

3. The optoelectronic device of claim 2 , wherein the first and second angles are equal to each other.

4. The optoelectronic device of claim 1 , wherein the junction is a junction of a planar structure type photodiode.

5. An optoelectronic device comprising:
a body of semiconductor material, the body including a first main surface;
a first region formed in the body;
a second region formed within the first region, wherein the first and second regions are of opposite conductivity types to form a junction between the first and second regions and a depletion region at the junction;
a recess extending from the first main surface of the body through the second region and into the first region to intersect the depletion region at a sidewall of the recess, wherein said recess is configured to expose the intersected depletion region at said sidewall to electromagnetic radiation;
wherein the recess includes a first side wall having a first angle relative to the first main surface of the body, said first angle being between, but not equal to either of, zero and ninety degrees;
a third region formed within the second region; and
wherein the first region corresponds to a collector, the second region corresponds to a base, and the third region corresponds to an emitter of a bipolar junction transistor.

6. The optoelectronic device of claim 5 wherein the third region comprises an annular region that surrounds the recess.

7. An optoelectronic device comprising:
a body of semiconductor material, the body including a first main surface;
a first region formed in the body;
a second region formed within the first region, wherein the first and second regions are of opposite conductivity types to form a junction between the first and second regions and a depletion region at the junction;
a recess extending from the first main surface of the body through the second region and into the first region to intersect the depletion region at a sidewall of the recess, wherein said recess is configured to expose the intersected depletion region at said sidewall to electromagnetic radiation;
wherein the recess includes a first side wall having a first angle relative to the first main surface of the body, said first angle being between, but not equal to either of, zero and ninety degrees;
a third region formed within the first region; and
wherein the first region corresponds to a body, the second region corresponds to a drain, and the third region corresponds to a source of a MOS transistor.

8. An optoelectronic device, comprising:
a body of semiconductor material, the body including a first main surface;
a first region having a first conductivity type formed in the body;
a second region of intrinsic material formed within the first region;
a third region having a second conductivity type opposite the first conductivity type formed within the second region to form a junction between the first, second and third regions and a depletion region at the junction;
a recess extending from the first main surface of the body through the second and third regions and into the first region to intersect the depletion region in the recess;
a top layer formed over the first main surface that includes a portion formed in the recess, the top layer having an index of refraction that is greater than an index of refraction of the body and being operable to expose the intersected depletion region to electromagnetic radiation propagating through the top layer;
wherein the recess includes a first side wall having a first angle relative to the first main surface of the body, said first angle being between, but not equal to either of, zero and ninety degrees.

9. The optoelectronic device of claim 8 , wherein the junction is PIN type junction comprising the first region being an N type semiconductor material, the second region being an intrinsic semiconductor material, and the third region being a P type semiconductor material.

10. The optoelectronic device of claim 8 ,
wherein the recess comprises a second side wall extending from the first main surface into the first region; and
wherein the recess comprises a third side wall extending within the first region between the first and second side walls, the third side wall having a surface that is substantially parallel to the first main surface.

11. The optoelectronic device of claim 10 , wherein the recess has a cross shape when viewed in a plan parallel to the first main surface.

12. An optoelectronic device comprising:
a body of semiconductor material, the body including a first main surface;
a first region having a first conductivity type formed in the body;
a second region of intrinsic material formed within the first region;
a third region having a second conductivity type opposite the first conductivity type formed within the second region to form a junction between the first, second and third regions and a depletion region at the junction;
a recess extending from the first main surface of the body through the second and third regions and into the first region to intersect the depletion region in the recess for exposure of the intersected depletion region to electromagnetic radiation;
wherein the recess includes a first side wall having a first angle relative to the first main surface of the body, said first angle being between, but not equal to either of, zero and ninety degrees; and
a top layer formed over the first main surface that includes a portion formed in the recess, the top layer having an index of refraction that is greater than an index of refraction of the body and being operable to enable electromagnetic radiation in the form of an optical signal to propagate through the top layer to the depletion region.

13. The optoelectronic device of claim 12 ,
wherein the recess has a second side wall extending from the first main surface into the first region;
wherein the portion of the top layer has a third side wall that is parallel to the first side wall; and
wherein the portion of the top layer has a fourth side wall that is parallel to the second side wall.

14. The optoelectronic device of claim 12 further comprising:
a first coating layer formed on the first main surface of the body with the top layer being formed on the first coating layer;
a second coating layer

Assignees

• St Microelectronics Srl

Inventors

• Pagani Alberto

Classifications

• H10F77/413

  directly associated or integrated with the devices, e.g. back reflectors (directly associated or integrated with photovoltaic cells H10F77/42) · CPC title

• H10F77/147

  Shapes of bodies · CPC title

• H10F77/30

  Coatings (arrangements for preventing damage to photovoltaic cells caused by corpuscular radiation H10F77/80) · CPC title

• H10F77/00

  Constructional details of devices covered by this subclass (constructional details of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title

• H10F39/18 Primary

  Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors · CPC title