TY - JOUR

T1 - Free-electron processes in amorphous semiconductors

AU - Singh, Jai

PY - 2003

Y1 - 2003

N2 - Several processes based on the free-electron concept are briefly reviewed in this paper. Using a quantum-tunneling model, a simple theory for determining the effective mass of charge carriers in amorphous semiconductors is presented. It is shown that a charge carrier has different effective masses in the extended and tail states, and that the sign of the effective mass changes as the charge carrier crosses its mobility edge. This is used to explain the anomalous Hall coefficient observed in a-Si : H. The theory is used to calculate Tauc's absorption relation, theoretically. It is found that deviations from the Tauc plot observed in some a-solids may be attributed to the photon-energy-dependent matrix element. Some transport properties of charge carriers are also considered. (c)� 2003 Kluwer Academic Publishers.

AB - Several processes based on the free-electron concept are briefly reviewed in this paper. Using a quantum-tunneling model, a simple theory for determining the effective mass of charge carriers in amorphous semiconductors is presented. It is shown that a charge carrier has different effective masses in the extended and tail states, and that the sign of the effective mass changes as the charge carrier crosses its mobility edge. This is used to explain the anomalous Hall coefficient observed in a-Si : H. The theory is used to calculate Tauc's absorption relation, theoretically. It is found that deviations from the Tauc plot observed in some a-solids may be attributed to the photon-energy-dependent matrix element. Some transport properties of charge carriers are also considered. (c)� 2003 Kluwer Academic Publishers.

KW - Amorphous materials

KW - Charge carriers

KW - Electron energy levels

KW - Photons

KW - Quantum-tunneling models

KW - Semiconductor materials

UR - http://www.scopus.com/inward/record.url?scp=0242380246&partnerID=8YFLogxK

M3 - Article

SN - 0957-4522

VL - 14

SP - 689

EP - 692

JO - Journal of Materials Science: Materials in Electronics

JF - Journal of Materials Science: Materials in Electronics

IS - 10-12

ER -