Microlenses of cmos image sensor and method for fabricating the same

Abstract

The invention relates to microlenses of a CMOS image sensor and a method of fabricating microlenses. The method includes at least one of the following steps: Forming a color filter array including a plurality of color filters on a semiconductor substrater. Forming on and / or over the color filter array a flattening layer to compensate for height differences between color filters. Forming a silicon oxide layer on and / or over the flattening layer. Forming on and / or over the silicon oxide layer, a plurality of photoresist patterns which correspond to the color filters, wherein the photoresist patterns may be separated from each other. Forming a plurality of CxFy-based polymer bumps surrounding the plurality of photoresist patterns using at least one process gas (e.g. C5F8, CH2F2, Ar, and / or O2). Etching the plurality of polymer bumps, the plurality of photoresist patterns, and the silicon oxide layer using an etching recipe having substantially the same etching selection ratio between the plurality of polymer bumps, the plurality of photoresist patterns, and the silicon oxide layer.

Description

[0001] This application claims priority from Korean Patent Application No. 10-2006-0072040 (filed on Jul. 31, 2006), the entire content of which is hereby incorporated by reference. technical field [0002] The invention relates to a microlens of a CMOS image sensor and a manufacturing method thereof. Background technique [0003] An image sensor is a device that receives light at a photodiode or phototransistor and uses an analog-to-digital converter (ADC) to convert the light into an electrical digital image signal. Two different image sensors are Complementary Metal Oxide Semiconductor (CMOS) devices and Charge Coupled Devices (CCD). CMOS devices can be used in small cameras with low power. In a CMOS device, a microlens (which may be exposed to air) focuses light onto a photodiode. A photodiode converts the collected light into an electrical signal. Multiple transistors can display the converted electrical signal as an image. [0004] A CMOS device may include a photo...

AI Technical Summary

Problems solved by technology

Difficulty standardizing microlens focal lengths due to variations in the manufacturing process, limiting microlens reproducibility

For example, it is difficult to standardize reflow processing

Images