Manufacturing method of solid-state imaging device

Abstract

Abstract PURPOSE:To facilitate the penetration effect of hydrogen and minimize a dark current without changing the photoelectric conversion characteristics of a photodiode by a method wherein a film made of material containing hydrogen atoms is provided on a part of a protective film and the film thickness on the upper part of the photodiode is reduced. CONSTITUTION:An Si3N4 film which is formed by plasma CVD is commonly used as a surface protection insulating film or the like and, as SiH4 is employed as material gas, usually contains 20-30% of the number of hydrogen atoms. At the surface near a P-N junction which is a main source of a dark current, the surface level is sufficiently reduced by hydrogen diffused from the Si3N4 film 9 and, on the other hand, the thickness of the Si3N4 film is reduced by partial etching on the upper part 10 of a photodiode which has influence upon photoelectric conversion characteristics such as spectral sensitivity characteristics. Therefore, a solid state image sensor in which the dark current is minimized, the variation of the spectral sensitivity characteristics caused by interference effect or the like is eliminated and further the variation of the characteristics caused by the penetration of Na ions, moisture and so forth is reduced and which provides high picture quality and high reliability can be realized.

Inventors

• 👤 Yoshimitsu Hiroshima
• 👤 広島　義光
• 👤 Shigenori Matsumoto
• 👤 松本　茂則
• 👤 Norihisa Mino
• 👤 規央 美濃

Bibliographic Details