A novel tungsten light-shield structure for high-density CCD image sensors

Author

Toyoda, Arata ; Suzuki, Yoshiaki ; Orihara, Kozo ; Hokari, Yasuaki

Author_Institution

NEC Corp., Kanagawa, Japan

Volume

38

Issue

5

fYear

1991

fDate

5/1/1991 12:00:00 AM

Firstpage

965

Lastpage

968

Abstract

A novel tungsten light-shield structure has been developed. Tungsten film properties, the device configuration with the tungsten light-shield structure, and experimentally achieved results regarding device characteristics are described. Optical measurement clarified that tungsten film has a sufficiently low transmittance value for practical use for more than 200-nm-thick film and is stable up to 1000°C. The good step coverage and low reflectance, such as 20-40% for aluminum, required for light-shield film were also obtained. A tungsten light-shield structure was applied to a 1/2-in format 668(H)-pixel×575(V)-pixel charge coupled-device (CCD) image sensor. An extremely low smear value, less than 0.001%, was obtained for a 300-nm film thickness

Keywords

CCD image sensors; tungsten; 0.5 in; 1/2-in format; 200 to 300 nm; 384100 pixel; 575 pixel; 668 pixel; CCD image sensors; W light shield; device characteristics; light-shield film; low reflectance; step coverage; Aluminum; Annealing; Charge coupled devices; Charge-coupled image sensors; HDTV; Optical films; Pixel; Reflectivity; TV; Tungsten;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.78366

Filename

78366