Back to results
US 2023/0420472 A1Published application
Image sensor
AssigneeSTMicroelectronics (Crolles 2) SAS
InventorAxel CROCHERIE
Life of this patent
Estimating the term…
Abstract
An image sensor is includes a plurality of pixels. Each of the pixels includes a silicon photoconversion region and a material that at least partially surrounds the photoconversion region. The material has a refraction index smaller than the refraction index of silicon, and the interface between the photoconversion region of the pixel and the material is configured so that at least one ray reaching the photoconversion region of the pixel undergoes a total reflection or a plurality of successive total reflections at the interface.
Claims16
A device, comprising:
- a substrate;
- a pixel on the substrate, the pixel having:
- a silicon photoconversion region extending upwardly from a rear surface to a front surface opposite to the rear surface and extends laterally between four lateral surfaces, the rear surface configured to receive at least one ray;
- a material at least partially surrounding the photoconversion region, the material having a refraction index smaller than a refraction index of silicon;
- and
- an antireflection layer in contact with only a portion of the rear surface of the photoconversion region, the antireflection layer being arranged to be crossed by the at least one ray.
3 more elements
A device, comprising:
- a substrate;
- a pixel on the substrate, the pixel having:
- a silicon photoconversion region;
- and
- a trench in the silicon photoconversion region, the trench having a first angled portion separated from a second angled portion by a central region;
- and
- an antireflection layer in the substrate, the first angled portion being closer to the antireflection layer than the second angled portion.
4 more elements
A method, comprising:
- manufacturing an image sensor by forming first trenches extending into a silicon substrate from a first surface of the silicon substrate, the first trenches having opposite oblique walls meeting at a bottom of the first trenches;
- forming second trenches laterally delimiting photoconversion regions of the sensor pixels, each of the second trenches extending into the silicon substrate from the bottom of a respective first trench;
- filling the first and second trenches with at least one material having a refraction index smaller than a refraction index of silicon;
- and
- forming third trenches extending into the silicon substrate from a second surface of the silicon substrate opposite to the first surface.
2 more elements
Dependencies are inferred from the claim text.