High-Speed Photodiodes in Standard CMOS Technology

1 Introduction 1.1 Outline 2 Short range optical interconnection 2.1 Why optical interconnection? 2.1.1 Electrical and Optical Interconnection - Similarities 2.1.2 Electrical and Optical Interconnection - Differences 2.2 Characteristics of light 2.3 Optical fiber types 2.3.1 Single-mode fibers 2.3.2 Multimode fibers 2.3.3 Plastic optical fibers 2.4 High intensity light sources 2.4.1 Lasers 2.4.2 Light Emitting Diodes (LEDs)2.5 Photodetectors - introduction 2.5.1 Ideal photodetector 2.5.2 Absorption of light in silicon 2.6 High-speed optical receivers in CMOS for [small lambda] = 850 nm-literature overview2.6.1 Using standard CMOS technology 2.6.2 CMOS technology modi.cation 3 CMOS photodiodes for [small lambda] = 850 nm 3.1 Introduction 3.2 Bandwidth of photodiodes in CMOS 3.2.1 Intrinsic (physical) bandwidth 3.2.2 Comparison between simulations and measurements 3.2.3 N+/p-substrate diode 3.2.4 P+/nwell/p-substrate photodiode with low-resistance substrate in adjoined-well technology 3.3 Intrinsic (physical) photodiode bandwidth3.4 Extrinsic (electrical) photodiode bandwidth 3.5 Noise in photodiodes 3.6 Summary and conclusions4 High data-rates with CMOS photodiodes 4.1 Introduction 4.2 Transimpedance amplifier design 4.2.1 Transimpedance ampli.ers and extrinsic bandwidth 4.2.2 Impact of noise: BER4.2.3 Noise of the TIA 4.3 Photodiode selection 4.4 Equalizer design 4.5 Robustness on spread and temperature 4.6 Experimental results 4.6.1 Circuit details and measurement setup 4.6.2 Optical receiver performance without equalizer 4.6.3 Optical receiver performance with equalizer 4.6.4 Robustness of the pre-amplifier: component spread 4.6.5 Robustness of the pre-amplifier: diode spread 4.7 Conclusions5 Bulk CMOS photodiodes for [small lambda]= 400 nm 5.1 Introduction 5.2 Finger nwell/p-substrate diode in adjoined-well technology 5.3 Finger n+/nwell/p-substrate diode 5.3.1 Time domain measurements 5.4 Finger n+/p-substrate photodiode in separate-well technology5.5 Finger p+/nwell/p-substrate in adjoined-well technology5.5.1 Time domain measurements 5.6 p+/nwell photodiode 5.7 Conclusion 6 Polysilicon photodiode 6.1 High-speed lateral polydiode 6.1.1 Pulse response of the poly photodiode 6.1.2 Di.usion current outside the depletion region 6.1.3 Frequency characterization of the polysilicon photodiode 6.2 Noise in polysilicon photodiodes 6.2.1 Dark leakage current in the polysilicon diode 6.3 Time domain measurements6.4 Quantum efficiency and sensitivity 6.5 Conclusion 7 CMOS photodiodes: generalized 7.1 Introduction 7.2 Generalization of CMOS photodiodes 7.3 Device layer - photocurrent amplitude 7.3.1 Device layer - photocurrent bandwidth 7.3.2 Substrate current-photocurrent amplitude 7.3.3 Substrate current-photocurrent bandwidth7.3.4 Depletion region current 7.3.5 Depletion region - photocurrent bandwidth 7.3.6 Total photocurrent 7.4 Analog equalization 7.5 Summary and Conclusions 8 Conclusions 8.1 Conclusions