This paper reports on atomic layer etching of several III-N materials such as GaN, AlN, AlGaN, and InAlGaN based on a sequential surface modification by chlorine adsorption followed by a low energy Ar plasma exposure to remove the modified layer using a reactive ion etching system. A study on the influence of several parameters, such as gas flow rates, removal step duration, RIE power and number of cycles on the etch per cycle, and the root-mean-square roughness, is performed. Low etch per cycle from 0.17 to 1.85 nm/cycle, respectively, for AlGaN and GaN and surfaces as smooth as the as-grown samples were obtained. The developed process is intended to be used for normally off GaN-based high electron mobility transistor processing.

1.
U. K.
Mishra
,
P.
Parikh
, and
Y.-F.
Wu
,
Proc. IEEE
90
,
6
(
2002
).
2.
F.
Medjdoub
,
J.-F.
Carlin
,
C.
Gaquiere
,
N.
Grandjean
, and
E.
Kohn
,
Open Electr. Electron. Eng. J.
13
,
1
(
2008
).
3.
O.
Ambacher
 et al,
J. Appl. Phys.
85
,
3222
(
1999
).
4.
W.
Lanford
,
T.
Tanaka
,
Y.
Otoki
, and
I.
Adesida
,
Electron. Lett.
41
,
449
(
2005
).
5.
Y.
Cai
,
Y.
Zhou
,
K. J.
Chen
, and
K. M.
Lau
,
IEEE Electron Device Lett.
26
,
435
(
2005
).
6.
X.
Hu
,
G.
Simin
,
J.
Yang
,
M.
Asif Khan
,
R.
Gaska
, and
M. S.
Shur
,
Electron. Lett.
36
,
753
(
2000
).
7.
L.
Trinh Xuan
 et al, in Proceedings of the 11th European Microwave Integrated Circuit Conference (EuMIC), London, UK, 3–4 October 2016 (IEEE,
2016)
, pp.
65
68
.
8.
J. R.
Mileham
,
S. J.
Pearton
,
C. R.
Abernathy
,
J. D.
MacKenzie
,
R. J.
Shul
, and
S. P.
Kilcoyne
,
J. Vac. Sci. Technol. A
14
,
386
(
1996
).
9.
M. E.
Lin
,
Z. F.
Fan
,
Z.
Ma
,
L. H.
Allen
, and
H.
Morkoç
,
Appl. Phys. Lett.
64
,
887
(
1994
).
10.
F.
Ren
,
J. R.
Lothian
,
Y. K.
Chen
,
J. D.
MacKenzie
,
S. M.
Donovan
,
C. B.
Vartuli
,
C. R.
Abernathy
,
J. W.
Lee
, and
S. J.
Pearton
,
J. Electrochem. Soc.
143
,
217
(
1996
).
11.
F.
Ren
,
J. R.
Lothian
,
S. J.
Pearton
,
C. R.
Abernathy
,
C. B.
Vartuli
,
J. D.
MacKenzie
,
R. G.
Wilson
, and
R. F.
Karlicek
,
J. Electron. Mater.
26
,
1287
(
1997
).
12.
Z.
Yatabe
,
Y.
Hori
,
S.
Kim
, and
T.
Hashizume
,
Appl. Phys. Express
6
,
016502
(
2013
).
13.
T.
Meguro
,
M.
Ishii
,
H.
Kodama
,
M.
Hamagaki
,
T.
Hara
,
Y.
Yamamoto
, and
Y.
Aoyagi
,
Jpn. J. Appl. Phys.
29
,
2216
(
1990
).
14.
K. K.
Ko
and
S. W.
Pang
,
J. Vac. Sci. Technol. B
11
,
2275
(
1993
).
15.
X.
Zhao
, “
Electric field engineering in GaN high electron mobility transistors
,”
Master’s thesis
(
Massachusetts Institute of Technology
,
2008
).
16.
K. J.
Kanarik
 et al,
J. Vac. Sci. Technol. A
35
,
05C302
(
2017
).
17.
T.
Ohba
,
W.
Yang
,
S.
Tan
,
K. J.
Kanarik
, and
K.
Nojiri
,
Jpn. J. Appl. Phys.
56
,
06HB06
(
2017
).
18.
C.
Kauppinen
,
S. A.
Khan
,
J.
Sundqvist
,
D. B.
Suyatin
,
S.
Suihkonen
,
E. I.
Kauppinen
, and
M.
Sopanen
,
J. Vac. Sci. Technol. A
35
,
060603
(
2017
).
19.
S. D.
Athavale
and
D. J.
Economou
,
J. Vac. Sci. Technol. B
14
,
3702
(
1996
).
You do not currently have access to this content.