Optical sensor and method of manufacture

Patent metadata

Field	Value
Publication number	US-10756228-B2
Application number	US-201815967242-A
Country	US
Kind code	B2
Filing date	Apr 30, 2018
Priority date	Apr 30, 2018
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

The present disclosure relates to a sensor comprising: an array of photodetectors comprising a first subarray of at least one photodetector and a second subarray of at least one photodetector; a first optical arrangement to direct incoming photons toward the first subarray; and a second optical arrangement to direct incoming photons toward the second subarray.

First claim

The invention claimed is:

1. A sensor comprising:
a die including:
a first subarray of a plurality of photodetectors; and
a second subarray of a plurality of photodetectors;

a substrate, the die being on the substrate;
a first spacer on the die;
a second spacer on the die, the first subarray being positioned between the first spacer and the second spacer;
a third spacer on the die, the second subarray being positioned between the second spacer and the third spacer;
a fourth spacer on the substrate, the fourth spacer offset from the die on the substrate, the fourth spacer being closer to the first spacer than to the third spacer;
a first optical arrangement aligned with the first subarray, the first spacer being between the first optical arrangement and the die;
a second optical arrangement aligned with the second subarray, the second spacer being between the first optical arrangement and the die, the second spacer being between the second optical arrangement and the die, the first and second optical arrangement include:
a first optical substrate on the first, second, and third spacer;

a third optical arrangement having:
a second optical substrate on the first and the fourth spacer; and

a photoemitter on the substrate.

2. The sensor according to claim 1 , further comprising a package with a front face, wherein the first optical arrangement includes a first aperture within the front face and the second optical arrangement includes a second aperture within the front face.

3. The sensor according to claim 1 , wherein the first optical arrangement includes a first converging optical element and the second optical arrangement includes a second converging optical element.

4. The sensor according to claim 3 , wherein the first subarray and the first converging optical element are aligned along an optical axis of the first converging optical element and wherein the second subarray and the second converging optical element are aligned along an optical axis of the second converging optical element.

5. The sensor according to claim 4 , wherein the optical axis of the first converging optical element is parallel to the optical axis of the second converging optical element.

6. The sensor according to claim 5 , wherein the first subarray and the second subarray are coplanar.

7. The sensor according to claim 6 , wherein the first subarray and the second subarray are arranged on a same substrate.

8. The sensor according to claim 3 , wherein:
the first converging optical arrangement includes a first aperture;
the second converging optical arrangement includes a second aperture;
the first subarray, the first converging optical element and the first aperture are aligned along an optical axis of the first converging optical element; and
the second subarray, the second converging optical element and the second aperture are aligned along an optical axis of the second converging optical element.

9. The sensor according to claim 1 , further comprising:
the third optical arrangement including a diverging optical element;
wherein the third optical arrangement is aligned with the photoemitter.

10. The sensor according to claim 9 , wherein:
the first optical arrangement includes a first converging optical element and the second optical arrangement includes a second converging optical element; and
an optical axis of the diverging optical element is parallel to an optical axis of the first converging optical element and an optical axis of the second converging optical element.

11. The sensor according to claim 9 , further comprising:
a package including a front face;
wherein the first optical arrangement includes a first aperture within the front face, the second optical arrangement includes a second aperture within the front face,
and the third optical arrangement includes a third aperture within the front face.

12. The sensor according to claim 11 , wherein the third aperture, the diverging optical element and the photoemitter are aligned along an optical axis of the diverging optical element.

13. The sensor according to claim 1 , wherein the sensor is a proximity sensor.

14. The sensor according to claim 1 , wherein each of the photodetectors of the first and second subarrays comprises a single photon avalanche diode.

15. An apparatus comprising:
a substrate;
a sensor coupled to the substrate and including:
a die including:
a first subarray of a plurality of photodetectors at a first surface; and
a second subarray of a plurality of photodetectors at the first surface;

a first spacer on the first surface of the die;
a second spacer on the first surface of the die, the first subarray being between the first spacer and the second spacer;
a third spacer on the first surface of the die, the second subarray being between the second spacer and the third spacer;
a first optical arrangement aligned with the first subarray, the first spacer being between the first optical arrangement and the die; and
a second optical arrangement aligned with the second subarray, the second spacer being between the first optical arrangement and the die, the second spacer being between the second optical arrangement and the die;
a fourth spacer on the substrate;
a light emitting element on the substrate and spaced from the die, the light emitting element being between the fourth spacer and the third spacer;
a first optical substrate on the first, second, and third spacers; and
a second optical substrate on the third and fourth spacers.

16. The apparatus according to claim 15 , wherein the apparatus comprises a mobile phone, a tablet computer, a laptop computer, a video game console, a smart card reader, a video camera, a television or a vehicle.

17. A method, comprising:
manufacturing a sensor by:
positioning a die on a support, the die having a first subarray of a plurality of photodetectors and a second subarray of a plurality of photodetectors;
forming a first spacer on the die, the first spacer being between the first su barray and the second subarray;
forming a second spacer on the die;
forming a third spacer on the die;
forming a fourth spacer on the support;
positioning a first optical element on the first, second, and third spacer;
positioning a first optical arrangement aligned with the first subarray, the first optical arrangement including a first portion of the first optical element;
positioning a second optical arrangement aligned with the second subarray, the second optical arrangement including a second portion of the first optical element, the first optical arrangement being separated from the die with the first spacer and the second optical arrangement being separated from the die with the second spacer;
positioning a fourth optical element on the third and fourth spacer; and
positioning a light emitting device on the support between the third spacer and the fourth spacer.

18. The method of claim 17 , further comprising:
providing a package with a front face, wherein:
the first optical arrangement comprises a first aperture within the front face and a first converging optical element;
the second optical arrangement comprises a second aperture within the front face and a second converging optical element;
the first subarray, first aperture, first converging optical element are aligned along an optical axis of the first converging optical element; and
the second subarray, second aperture, and second converging optical element are aligned along an optical axis of the second converging optical element.

Assignees

• Stmicroelectronics (Research & Development) Ltd

Inventors

• Downing James Peter Drummond

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

• H10F39/107

  having multiple elements covered by H10F30/00 in a repetitive configuration, e.g. radiation detectors comprising photodiode arrays · CPC title

• H10F39/103

  the at least one element covered by H10F30/00 having potential barriers, e.g. integrated devices comprising photodiodes or phototransistors · CPC title

• H10F30/225

  the potential barrier working in avalanche mode, e.g. avalanche photodiodes · CPC title

• H10F39/804

  Containers or encapsulations · CPC title