WORKSHOP PAPER
Fast Charge Transfer in 100 µm long PPD Pixels
Abstract
In this paper we present a photodiode structure for fast charge transfer in narrow and elongated pixels. For applications requiring high frame rate and elongated pixels, charge diffusion in photodiode limits the transfer efficiency (transfer time < 1µs). We solve this by creating an electrostatic potential gradient in the direction of transfer by exploiting the proximity effect of implanted regions on the pinning voltage. The proposed method is realized in a pixel with dimension of 7 µm x 100 µm. The method does not influence the quantum efficiency and uses a standard 0.18 CIS process.Keywords
Fast charge transfer, Photodiode structure, Electrostatic potential gradient,References
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