STUDY OF THE SCOPES AND THE VALIDITY OF THE SIMMON-TAYLORS APPROACH IN THE MODELING OF DISORDERED SEMICONDUCTOR DEVICES

M. DE GREEF; H. RAMIREZ; F.A. RUBINELLI

Anales AFA

Asociación Física Argentina

Lugar: Tandil; Año: 2012 vol. 23 p. 60 - 64

0327-358X

The performance of amorphous materials based electronic device is highly dependent on the density of states present in the band gap. This density of states contains two exponentially decreasing tails and deep states. Charge trapping in localized gap states and recombination of electron-hole pair through these states are usually described by the Schockley-Read-Hall (SRH) formalism. The equations derived in the SRH statistics can be simplified by Simmon-Taylor’s approach, especially using so called “0K” approximation. Although the validity of these approaches were discussed in the literature on semiconductor materials, there is no a systematical study where these algorithms were included in a device oriented numerical code in order to compare the differences introduced by the approximations. In this paper, the approaches of Simmon-Taylor were implemented in our code D-AMPS and the current-voltage and spectral responses curves were obtained with and without these approximations under different sceneries and other electric parameters. Our results indicate that the Simmon-Taylor approach is acceptable when the device is forward biased, while the 0K approach presents some problems.