Three-dimensional structures for high saturation signals and crosstalk suppression in 1.20 #x03BC;m pixel back-illuminated CMOS image sensor

摘要

We propose two technologies, vertical transfer gate (VTG) and buried shielding metal (BSM), that can be applied to 1.20 μm pixel back-illuminated CMOS image sensor (BI-CIS). With the VTG and BSM, the new pixel design exhibited 60% higher saturation signals and 50% lower crosstalk at wide chief ray angle (CRA). Even though both technologies have a three-dimensional structure formed on Si substrate, our process technology enabled them to be applied without increasing white blemish count or dark current degradation.