Si基单片集成850nm光接收芯片研究

Abstract

设计并制备了一种SI基单片集成850nM光接收芯片,包括“P+/n-EPI/bn+“结构的光电探测器(Pd)、跨阻前置放大电路及其后续处理电路。分析了Pd的结构,并对其光谱响应及频率响应进行模拟,在2.0V偏压下,Pd在850nM的响应度为0.131A/W,截止频率为400 MHz。采用0.5μM bCd(bIPOlAr、CMOS和dMOS)工艺流片,光接收芯片面积约为900μMx1 100μM。测试结果表明,Pd暗电流为PA量级,响应度为0.12A/W。光接收芯片在155 Mb/S速率及误码率(bEr)小于10-9情况下,灵敏度为-12.0dbM;在622 Mb/S速率及bEr小于10-9情况下,灵敏度为-10.0dbM,并能得到清晰的眼图。将该光接收芯片封装后接入光接收模块,进行点对点光互联实验,获得很好的光信号通路。

A silicon-based monolithic 850 nm optical receiver is proposed,including a P+/N-EPI/BN+ photodetector(PD),a tranimpedance preamplifier and a relevant processing circuit.The structure of photodetector is analyzed,and its spectral response and frequency response are simulated.The responsivity is 0.131 A/W and the cut-off frequency is 400 MHz for 850 nm under 2.0 V reverse bias.The actual chip area of the optical receiver is about 900 μm×1 100 μm with 0.5 μm BCD(bipolar,CMOS and DMOS) process.Measurement results show that the dark current of photodetector is at pA magnitude and the responsivity is 0.12 A/W.The sensitivity is-12.0 dBm at 155 Mb/s and BER is less than 10-9,and the sensitivity is-10.0 dBm at 622 Mb/s and BER is less than 10-9.A clear eye diagram is demonstrated for 622 Mb/s pseudorandom binary sequence.A good optical signal path in point-to-point experiment can be obtained by implanting packaged optical receiver in commercial optical receiver module.