Multi-pixel detector and associated method for increasing angular sensitivity

Patent metadata

Field	Value
Publication number	US-10475838-B2
Application number	US-201715714502-A
Country	US
Kind code	B2
Filing date	Sep 25, 2017
Priority date	Sep 25, 2017
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

An image sensor includes a multi-pixel detector. The multi-pixel detector includes a first pixel formed in a substrate and having a first photodiode region, a second pixel formed in the substrate adjacent to the first pixel and having a second photodiode region, and a microlens above both the first pixel and the second pixel. The microlens includes (a) in a first cross-sectional plane perpendicular to a top surface of the substrate and including both the first and the second photodiode regions, a first height profile having N1 local maxima, and (b) in a second cross-sectional plane perpendicular to the first cross-sectional plane and the top surface and including only one of the first and the second photodiode regions, a second height profile having N2>N1 local maxima.

First claim

What is claimed is:

1. An image sensor with a multi-pixel detector, comprising:
a first pixel formed in a substrate and having a first photodiode region;
a second pixel formed in the substrate adjacent to the first pixel and having a second photodiode region; and
a microlens above both the first pixel and the second pixel and having
(a) in a first cross-sectional plane perpendicular to a top surface of the substrate and including both the first and the second photodiode regions, a first height profile having N 1 local maxima, N 1 ≥1, and
(b) in a second cross-sectional plane perpendicular to the first cross-sectional plane and the top surface and including only one of the first and the second photodiode regions, a second height profile having N 2 >N 1 local maxima.

2. The image sensor of claim 1 ,
the first height profile having N 1 =1 local maxima and being characterized by first radius of curvature R 1 ; and
the second height profile including a first local maxima and a second local maxima corresponding to respective radii of curvature R 21 <R 1 and R 22 <R 1 .

3. The image sensor of claim 2 , the radius of curvature R 1 =730±70 nanometers.

4. The image sensor of claim 2 , the radii of curvature R 21 and R 22 being equal to within ten percent of (R 21 +R 22 )/2.

5. The image sensor of claim 2 , the radii of curvature R 21 and R 22 being equal to 580±60 nm.

6. The image sensor of claim 1 , the microlens having a maximum thickness of 730±70 nanometers.

Assignees

• Omnivision Tech Inc

Inventors

• Lu Chen-Wei
• Qian Yin
• Pang Chin Poh
• Zhang Boyang

Classifications

• H01L27/14685

  Electricity · mapped topic

• H01L27/14621

  Electricity · mapped topic

• H01L27/14627 Primary

  Electricity · mapped topic

• H10F39/8053

  Colour filters · CPC title

• H10F39/802

  Geometry or disposition of elements in pixels, e.g. address-lines or gate electrodes · CPC title