Back-illuminated Structure
Technology
Common Technology of Image Sensors

Back-illuminated Structure

  • Home
  • Technology
  • Common Technology of Image Sensors
  • Back-illuminated Structure

Overview

In 2009, Sony Semiconductor Solutions Corporation(SSS) developed a back-illuminated CMOS image sensor product with twice the sensitivity of conventional products. Compared to conventional CMOS image sensors with a front-illuminated structure, it has achieved roughly double the sensitivity while also reducing noise. Emitting light from the back side of the silicon substrate has made it possible to increase the amount of light entering each pixel without being obstructed by metal wiring or transistors, allowing it to reduce the degradation of sensitivity caused by different optical angles. It can capture smooth, high resolution images even in settings with dark environments such as night views.

Overview

Technical Features

Unique photo-diode structure optimized for a back-illuminated structure

A back-illuminated structure minimizes the degradation of sensitivity caused by different optical angles, while also increasing the amount of light that enters each pixel thanks to the release from obstacles such as metal wiring and transistors that have been moved to the other side of the silicon substrate. However, compared to conventional front-illuminated structures, back-illuminated structures generally cause problems that result from their device structure and manufacturing process, such as noise, dark current, defective pixels, or color mixture, that lead to image degradation and also cause a decrease in the signal-to-noise ratio.

To overcome this, SSS has developed a unique photo-diode structure optimized for a back-illuminated structure, that achieves higher sensitivity and lower random noise by reducing noise, dark current and defect pixels. Additionally, SSS's advanced technologies such as high-precision alignment have addressed color mixture problems.

Related Products & Solutions

Contact Us

For inquiries about Sony Semiconductor Solutions Group and products / solutions, specifications, quotation / purchase requests, etc., please contact us using the Inquiry form from the button below.