<title>True two-phase CCD image sensors employing a transparent gate</title>

Abstract

This paper describes the performance of a family of full-frame sensor designs where a transparent electrode replaces one of the polysilicon gates. The sensors are all fabricated with a true two-phase buried channel CCD process that is optimized for operation in multi-pinned phase (MPP) mode for low dark current. The true two-phase architecture provides many advantages such as progressive scan, square pixels, high charge capacity, and simplified drive requirements. The uncomplicated structure allows large area arrays to be fabricated with reasonable yield. Inclusion of a transparent gate increases the response by a factor of 10 at 400 nm and 50% at 600 nm.

DEVELOPMENTS AND APPLICATIONS OF HIGH-PERFORMANCE CCD AND CMOS IMAGING ARRAYS

“…It also provides better index matching to silicon, reducing the amount of light lost, owing to reflection of the sensor surface. The advantages of increased blue response of ITOs in digital photography propelled Eastman Kodak Company in 1999 to commercialize a process in which ITO is used for one of the electrodes in each pixel (5). In 2002, Kodak introduced sensors in which light is focused onto the single ITO phase using a microlens array-the first use of a microlens on a traditional CCD pixel.…”