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In optical applications where avalanche photodiodes (APDs) provide the benefit of high sensitivity, Sb-based materials systems such as AlInAsSb and AlGaAsSb have shown extremely low excess noise factors. The Monte Carlo (MC) model described in this work reveals the effect of high alloy scattering on the excess noise factor in these material systems. A comparison between the excess noise factor of different combinations of scattering rates is investigated. Furthermore, the ionization path length probability distribution is presented for AlInAsSb APDs with different scattering mechanisms. Good agreement is achieved between simulation results and experimental measurements.
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Understanding the Role of Minigaps in APDs: Towards Designing a Better Photodetector
Superior performance of digital alloy APDs is attributed to the formation of "minigaps" in the material band-structure. However, no improvement is observed in dilute nitride APDs in presence of minigaps. We propose criteria which can judge the effectiveness of these minigaps.
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- Award ID(s):
- 1936016
- PAR ID:
- 10184798
- Date Published:
- Journal Name:
- 2019 IEEE Photonics Conference (IPC)
- Page Range / eLocation ID:
- 1 to 2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IPCon.2019.8908355
