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arXiv · 1407.3712

Development of a highly pixelated direct charge sensor, Topmetal-I, for ionizing radiation imaging

Yan Fan·Chaosong Gao·Guangming Huang·Xiaoting Li·Yuan Mei·Hua Pei·Quan Sun·Xiangming Sun·Dong Wang·Zhen Wang·Le Xiao·Ping Yang
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Abstract

Using industrial standard 0.35μm CMOS Integrated Circuit process, we realized a highly pixelated sensor that directly collects charge via metal nodes placed on the top of each pixel and forms two dimensional images of charge cloud distribution. The first version, Topmetal-I, features a 64x64 pixel array of 80μm pitch size. Direct charge calibration reveals an average capacitance of 210fF per pixel. The charge collection noise is near the thermal noise limit. With the readout, individual pixel channels exhibit a most probable equivalent noise charge of 330e-.

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Yan Fan, Chaosong Gao, Guangming Huang, Xiaoting Li, Yuan Mei, Hua Pei, Quan Sun, Xiangming Sun, Dong Wang, Zhen Wang, Le Xiao, Ping Yang. 2014-07-14. Development of a highly pixelated direct charge sensor, Topmetal-I, for ionizing radiation imaging. https://arxiv.org/abs/1407.3712

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