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A practical quantitative model is presented to account for the I–V characteristics of pin diodes based on epitaxial Ge-like materials. The model can be used to quantify how the different material properties and recombination mechanisms affect the diode performance. The importance of dislocations, non-passivated defects, and residual intrinsic layer doping in determining the qualitative shape of the I–V curves is discussed in detail. Examples are shown covering literature diodes as well as diodes fabricated with the purpose of validating the theoretical effort.
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A practical theoretical model for Ge-like epitaxial diodes. II. Matching the experimental optical responsivity in pin devices
A theoretical model that can be used to simultaneously fit the I–V characteristics and spectral optical responsivity of Ge-like pin diodes is described in detail and validated experimentally using specially fabricated Ge- and Ge1−ySny devices. The model combines a numerical solution of the basic semiconductor transport equations with a rigorous calculation of the optical generation rate that accounts for multiple reflections in the device structure multilayers. The results can be used to quantify the reduction of photocurrent associated with recombination centers for full optimization of the device structure.
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- PAR ID:
- 10575040
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 137
- Issue:
- 9
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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