Title :
Light guide for pixel crosstalk improvement in deep submicron CMOS image sensor
Author :
Hsu, T.H. ; Fang, Y.K. ; Lin, C.Y. ; Chen, S.F. ; Lin, C.S. ; Yaung, D.N. ; Wuu, S.G. ; Chien, H.C. ; Tseng, C.H. ; Lin, J.S. ; Wang, C.S.
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Taiwan, Taiwan
Abstract :
Light guide, a novel dielectric structure consisting of PE-Oxide and FSG-Oxide, has been developed to reduce crosstalk in 0.18-μm CMOS image sensor technology. Due to the difference in refraction index (1.46 for PE-Oxide and 1.435 for FSG-Oxide), major part of the incident light can be totally reflected at the interface of PE-Oxide/FSG-Oxide, as the incidence angle is larger than total reflection angle. With this light guide, the pixel sensing capability can be enhanced and to reduce pixel crosstalk. Small pixels with pitch 3.0-μm and 4.0-μm have been characterized and examined. In 3.0-μm pixel, optical crosstalk achieves 30% reduction for incidence angle of light at 10/spl deg/.
Keywords :
CMOS image sensors; dielectric devices; dielectric properties; optical crosstalk; FSG-oxide; PE-oxide; crosstalk reduction; deep submicron CMOS image sensor; dielectric structure; incidence angle; light guide; pixel crosstalk improvement; refraction index; total reflection angle; CMOS image sensors; CMOS logic circuits; CMOS technology; Colored noise; Computational Intelligence Society; Image sensors; Optical crosstalk; Optical refraction; Pixel; Scanning electron microscopy;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2003.821597
