[14a-1C-1~10] 13.4 Si wafer processing /MEMS/Integration technology

[14a-1C-2] Three-Dimensional Integration of Pulse-Frequency-Modulation A/D Converters

〇Masahide Goto¹, Kei Hagiwara¹, Yoshinori Iguchi¹, Hiroshi Ohtake¹, Takuya Saraya², Masaharu Kobayashi², Eiji Higurashi², Hiroshi Toshiyoshi², Toshiro Hiramoto² (1.NHK STRL, 2.Univ. of Tokyo)

Keywords:image sensor,A/D converter,3D stacking

We have studied a pixel-parallel three-dimensional (3D) integrated CMOS image sensor that meets the demand for high resolution and high frame rate. We have designed a pixel circuit with a pulse-frequency-modulation type A/D converter. Measurement results of the developed device confirmed that the frequency of the output pulses increases in proportional to the light intensity. We also designed a pulse counter and confirmed its operation as designed. This result shows a promise as pixel-parallel image sensor of next generation.