An electrical conduction model for polycrystalline (PX) GaAs is presented to explain the electrical properties of this material. It is predicted that these properties cannot be explained without considering an additional rectangular potential barrier (qϕ) at the grain boundary and an additional mechanism of carrier transport (two-step tunneling process via grain boundary states) across the grain boundaries. It is demonstrated that the grain-boundary material in polycrystalline GaAs films is disordered in nature. Present computations have shown that the dependence of qϕ on doping density is very complicated and it is controlled by the processes of As clustering, and segregation of dopant as well as As atoms at the grain boundaries. It is also shown that the dopant segregation mechanism is present only in n-type PX-GaAs films, whereas it is absent in p-type samples. The dependence of carrier mobility and resistivity of this material on the doping density, temperature, and grain size has also been studied. A satisfactory agreement is observed between the theoretically computed results and available experimental data.

1.
K. N.
Bhat
, in
Proceedings of International Conference on Physics and Technology of Compensated Semiconductors, Madras
(
Madras, India
, Feb.
1985
), p.
79
.
2.
W.
Siegel
,
G.
Kuehnel
, and
H. A.
Schneider
,
Phys. Status Solidi A
87
,
673
(
1985
).
3.
H. Y.
Lo
,
J. M.
Hong
,
C. M.
Wu
, and
S.
Wang
,
IEEE Electron Device Lett.
EDL-7
,
586
(
1980
).
4.
J. J. J.
Yang
,
P. D.
Dapkus
,
R. D.
Dupuis
, and
R. D.
Yingling
,
J. Appl. Phys.
51
,
3794
(
1980
).
5.
S. S.
Negi
and
D. P.
Joshi
, in “
Semiconductor Materials and Devices
,”
Proceedings of the National Conference on Recent Developments in Semiconductors, I.I.T. Delhi
(
New Delhi
, 20–22 June 1995), edited by
O. P.
Agnihotri
and
V. K.
Jain
(
Narosa
,
New Delhi
,
1998
).
6.
N. C. C.
Lu
,
L.
Gerzberg
,
C. Y.
Lu
, and
J. D.
Meindl
,
IEEE Electron Device Lett.
ED-28
,
818
(
1981
).
7.
M. M.
Mandurah
,
K. C.
Saraswat
, and
T. I.
Kamins
,
IEEE Electron Device Lett.
ED-28
,
1163
(
1981
).
8.
M. M.
Mandurah
,
K. C.
Saraswat
, and
T. I.
Kamins
,
IEEE Electron Device Lett.
ED-28
,
1171
(
1981
).
10.
D. P.
Bhatt
and
D. P.
Joshi
,
J. Appl. Phys.
68
,
2338
(
1990
).
11.
D. P.
Joshi
and
R. S.
Srivastava
,
J. Appl. Phys.
56
,
2375
(
1984
).
12.
D. P.
Joshi
and
R. S.
Srivastava
,
IEEE Electron Device Lett.
ED-31
,
920
(
1984
).
13.
N. C. C.
Lu
,
L.
Gerzberg
,
C. Y.
Lu
, and
J. D.
Meindl
,
IEEE Electron Device Lett.
EDL-1
,
38
(
1980
).
14.
S. S.
Negi
,
D. P.
Joshi
, and
D. P.
Bhatt
, in
Optics and Optoelectronics
,
Proceedings of the XXXIIIth National Symposium of Optical Society of India, 14–16 March 1996
(
IRDE
,
Raipur, Dehradun, India
,
1996
).
15.
C. M.
Wu
and
E. S.
Yang
,
Appl. Phys. Lett.
40
,
49
(
1982
).
17.
C. M.
Wu
and
E. S.
Yang
,
IEEE Electron Device Lett.
ED-29
,
1598
(
1982
).
18.
C. H.
Seager
and
D. S.
Ginley
, Final research report covering work completed from Feb.–Dec. 1979,
Sandia National Laboratories
, Livermore, CA.
19.
K.
Kato
and
Y.
Amemiya
,
IEEE Electron Device Lett.
ED-29
,
1156
(
1982
).
20.
J.
Shewchun
,
A.
Waxman
, and
G.
Warfield
,
Solid-State Electron.
10
,
1165
(
1967
).
21.
M. S.
Rodder
and
D. A.
Antoniadis
,
Mater. Res. Soc. Symp. Proc.
106
,
77
(
1988
).
22.
D. P.
Bhatt
and
D. P.
Joshi
,
J. Appl. Phys.
68
,
2338
(
1990
).
23.
M. J.
Deen
,
A. A.
Naem
, and
C. J.
Chee
,
J. Appl. Phys.
76
,
5253
(
1994
).
24.
A. L.
Fahrenbruch
and
R. H.
Bube
,
Fundamentals of Solar Cells
(
Academic
,
New York
,
1983
).
25.
S. M.
Sze
,
Physics of Semiconductor Devices
(
Wiley
,
New York
,
1987
).
26.
J. H.
Epple
,
K. L.
Chang
,
C. F.
Xu
,
G. W.
Pickrell
,
K. Y.
Chang
, and
K. C.
Hsiesh
,
J. Appl. Phys.
93
,
5331
(
2003
).
27.
Unpublished work.
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