Granted Patent B2

US 12,635,268 · App. 18/144,779 · Granted May 19, 2026

Inventors: Yen-Cheng Lu (Zhubei City, TW); Yun-Chung Na (San Jose, CA)

Assignee: Artilux, Inc.

H10F30/2255H10F39/18H10F39/8033H10F39/805H10F77/933

Abstract

Claims (39)

1 . An optical sensor, comprising:

a first photo-detecting element comprising:

an absorption region comprising p-doped germanium, the absorption region configured to receive an optical signal and to generate photo-carriers in response to the optical signal; and

a silicon substrate in contact with the absorption region via a heterointerface, the silicon substrate comprising:

a plurality of p-doped regions;

a plurality of n-doped regions, wherein the plurality of p-doped regions are formed closer to the heterointerface than the plurality of n-doped regions are;

one or more multiplication regions formed between the plurality of p-doped regions and the plurality of n-doped regions, wherein the one or more multiplication regions are configured to amplify a portion of the photo-carriers drifting from the absorption region to the plurality of p-doped regions; and

an n-doped carrier conducting region in contact with the absorption region to form the heterointerface and in contact with the plurality of p-doped regions,

wherein a maximum distance between two outermost p-doped regions of the plurality of p-doped regions is greater than a width of the n-doped carrier conducting region.

2 . The optical sensor of claim 1 , wherein the plurality of p-doped regions are at least partially overlapped with the n-doped carrier conducting region.

3 . The optical sensor of claim 1 , wherein a ratio between a first doping concentration of the absorption region and a second doping concentration of the n-doped carrier conducting region at the heterointerface is equal to or greater than 10.

4 . The optical sensor of claim 3 , wherein the absorption region further comprises a first p-doped contact region coupled to a first electrode, wherein the plurality of n-doped regions are coupled to a second electrode, and wherein the first p-doped contact region has a third doping concentration higher than the first doping concentration.

5 . The optical sensor of claim 4 , wherein the plurality of p-doped regions have a fourth doping concentration that is higher than the second doping concentration of the n-doped carrier conducting region.

6 . The optical sensor of claim 4 , wherein the first photo-detecting element is configured to operate in a Geiger mode under a reverse bias between the first electrode and the second electrode.

7 . The optical sensor of claim 4 , wherein the plurality of p-doped regions are coupled to a third electrode.

8 . The optical sensor of claim 1 , wherein the plurality of p-doped regions and the plurality of n-doped regions are arranged in a staggered arrangement.

9 . The optical sensor of claim 1 , wherein the absorption region is doped with a graded doping profile.

10 . The optical sensor of claim 1 , wherein the absorption region is at least partially embedded in the silicon substrate.

11 . The optical sensor of claim 1 ,

wherein the silicon substrate comprises a first surface and a second surface that is opposite to the first surface,

wherein the plurality of p-doped regions are formed closer to the first surface than the plurality of n-doped regions, and

wherein the first photo-detecting element further comprises one or more optical structures formed on the second surface configured to receive the optical signal.

12 . The optical sensor of claim 11 , wherein the one or more optical structures comprise one or more lenses.

13 . The optical sensor of claim 1 , comprising a sensor array comprising one-dimensional (1D) or two-dimensional (2D) array of photo-detecting elements formed on the silicon substrate, the 1D or 2D array of photo-detecting elements including the first photo-detecting element.

14 . The optical sensor of claim 1 , wherein a thickness of the one or more multiplication regions is in a range from 100 nm to 500 nm.

15 . The optical sensor of claim 1 , wherein at least 50% of the absorption region is doped with a doping concentration that is equal to or greater than 1×10 16 cm −3 .

16 . A system comprising:

an optical transmitter configured to emit an optical signal having a peak wavelength greater than 900 nm; and

an optical sensor, comprising:

a first photo-detecting element comprising:

an absorption region comprising p-doped germanium, the absorption region configured to receive the optical signal and to generate photo-carriers in response to the optical signal; and

a silicon substrate in contact with the absorption region via a heterointerface, the silicon substrate comprising:

a plurality of p-doped regions;

a plurality of n-doped regions, wherein the plurality of p-doped regions are formed closer to the heterointerface than the plurality of n-doped regions;

one or more multiplication regions formed between the plurality of p-doped regions and the plurality of n-doped regions, wherein the one or more multiplication regions are configured to amplify a portion of the photo-carriers drifting from the absorption region to the plurality of p-doped regions; and

an n-doped carrier conducting region in contact with the absorption region to form the heterointerface and in contact with the plurality of p-doped regions,

wherein a maximum distance between two outermost p-doped regions of the plurality of p-doped regions is greater than a width of the n-doped carrier conducting region.

17 . The system of claim 16 , wherein the system is a mobile device, a wearable device, or a robotic device.

18 . The system of claim 16 , wherein the optical transmitter comprises one or more light emitting diodes or one or more vertical-cavity surface-emitting lasers.

Assignments (1)

Continuity (6)

References Cited (278)