Optoelectronic Simulation of PhotoDetectors

Tarun ParmarMicrorelectronic Engineering

R.I.T.

Outline

• Introduction• Comparison of Photodetectors• Photon detection• Device Simulation • Optoelectronic Device Simulator• Results

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Introduction

• The poster presents simulation of recombination rate and quantum efficiency of an photodetector (photodiode) being fabricated at RIDL.

• Simulated total integrated recombination rate significantly contributes to the reverse diode leakage current.

• Quantum efficiency is defined as the ratio of the number of carriers detected at a given photodetector electrode divided by the number of incident photons on the detector.

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Comparison of Photodetectors

Generic Operating Parameters of Si, Ge, and GaAs pin Photodiodes

[Source: Optical Communications Essentials, Gerd Keiser, pp 113.]4

Photon Detection• pinpin photodiode operated in reverse bias

– pp+ – high acceptor concentration

– iintrinsic (lightly) doped material

– nn+ –high donor concentration

• I-VI-V characteristics of pin photodiode:– (1) with no light– (2) with light

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Device Simulation

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Luminous is an advanced simulator used to model absorption and photogeneration in semiconductor devices

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Optoelectronic Device Simulator

Silvaco Athena simulation tool Silvaco Athena simulation tool

Process simulation uses Athena &

Electrical simulation uses Atlas, Luminous

Graphs are generated using Tonyplot

Tonyplot Results (1)

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Quantum Efficiency

Recombination Rate0.258 e-/sec/pixel

Tonyplot Results (2)

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Electric field in 2D Electric field in 3D