# The mathematical modeling of time-dependent photoconductive phenomena in semiconductors

## Abstract

This dissertation presents results pertaining to the mathematical modeling of semiconductor photoconductors and includes the formulation, analysis, and solution of photoconductive device model equations. The fundamental semiconductor device equations of continuity and transport are derived for the case of a material which contains a large density of deep-level impurities. Electron and hole trapping on deep-level impurities is accounted for by trapping-kinetics rate equations. The coupling between carrier drift and the electric field is completed through Poisson's equation. Simple, nonlinear model equations are presented for bulk-material response based on the dynamics of electron and hole trapping and recombination on deep-level impurities. The characteristics of the solution to these model equations are observed to depend strongly on the excitation intensity. These model equations qualitatively reproduce observed experimental behavior of an iron-doped indium phosphide photoconductor. A theory of the effect of deep-level centers on the generation-recombination noise and responsivity of an intrinsic photoconductor is presented. Photoconductive device model equations based on time-dependent, convective/diffusive transport equations are presented. The system of model equations is solved numerically with boundary conditions that represent ideal ohmic contacts. Computed results are presented for different photoconductor lengths and bias voltages with spatially uniform, rectangular light-pulse illumination.

- Authors:

- Publication Date:

- Research Org.:
- Los Alamos National Lab., NM (USA)

- OSTI Identifier:
- 6291269

- Report Number(s):
- LA-11044-T

ON: DE87012049

- DOE Contract Number:
- W-7405-ENG-36

- Resource Type:
- Technical Report

- Resource Relation:
- Other Information: Thesis (Ph.D.). Portions of this document are illegible in microfiche products. Thesis. Submitted to Univ. of Arizona, Tucson

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 42 ENGINEERING; INDIUM PHOSPHIDES; PHOTOCONDUCTIVITY; MERCURY TELLURIDES; PHOTOCONDUCTORS; MATHEMATICAL MODELS; CONTINUITY EQUATIONS; GREEN FUNCTION; HOLE MOBILITY; IMPURITIES; IRON; MAXWELL EQUATIONS; NOISE; POISSON EQUATION; TRAPPING; CHALCOGENIDES; DIFFERENTIAL EQUATIONS; ELECTRIC CONDUCTIVITY; ELECTRICAL PROPERTIES; ELEMENTS; EQUATIONS; FUNCTIONS; INDIUM COMPOUNDS; MERCURY COMPOUNDS; METALS; MOBILITY; PARTIAL DIFFERENTIAL EQUATIONS; PHOSPHIDES; PHOSPHORUS COMPOUNDS; PHYSICAL PROPERTIES; PNICTIDES; TELLURIDES; TELLURIUM COMPOUNDS; TRANSITION ELEMENTS; 420800* - Engineering- Electronic Circuits & Devices- (-1989)

### Citation Formats

```
Iverson, A E.
```*The mathematical modeling of time-dependent photoconductive phenomena in semiconductors*. United States: N. p., 1987.
Web.

```
Iverson, A E.
```*The mathematical modeling of time-dependent photoconductive phenomena in semiconductors*. United States.

```
Iverson, A E. 1987.
"The mathematical modeling of time-dependent photoconductive phenomena in semiconductors". United States.
```

```
@article{osti_6291269,
```

title = {The mathematical modeling of time-dependent photoconductive phenomena in semiconductors},

author = {Iverson, A E},

abstractNote = {This dissertation presents results pertaining to the mathematical modeling of semiconductor photoconductors and includes the formulation, analysis, and solution of photoconductive device model equations. The fundamental semiconductor device equations of continuity and transport are derived for the case of a material which contains a large density of deep-level impurities. Electron and hole trapping on deep-level impurities is accounted for by trapping-kinetics rate equations. The coupling between carrier drift and the electric field is completed through Poisson's equation. Simple, nonlinear model equations are presented for bulk-material response based on the dynamics of electron and hole trapping and recombination on deep-level impurities. The characteristics of the solution to these model equations are observed to depend strongly on the excitation intensity. These model equations qualitatively reproduce observed experimental behavior of an iron-doped indium phosphide photoconductor. A theory of the effect of deep-level centers on the generation-recombination noise and responsivity of an intrinsic photoconductor is presented. Photoconductive device model equations based on time-dependent, convective/diffusive transport equations are presented. The system of model equations is solved numerically with boundary conditions that represent ideal ohmic contacts. Computed results are presented for different photoconductor lengths and bias voltages with spatially uniform, rectangular light-pulse illumination.},

doi = {},

url = {https://www.osti.gov/biblio/6291269},
journal = {},

number = ,

volume = ,

place = {United States},

year = {1987},

month = {7}

}