Deep Trench Isolation and Inverted Pyramid Array Structures Used to Enhance Optical Efficiency of Photodiode in CMOS Image Sensor via Simulations.

The photodiode in the backside-illuminated CMOS sensor is modeled to analyze the optical performances in a range of wavelengths (300-1100 nm). The effects of changing in the deep trench isolation depth (DTI) and pitch size (d) of the inverted pyramid array (IPA) on the peak value () of optical efficiency (OE) and its wavelength region are identified first. Then, the growth ratio (GR) is defined for the change in these wavelength ranges to highlight the effectiveness of various DTI and d combinations on the and evaluate the difference between the pixel arrays with and without the DTI + IPA structures.