Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-02T22:03:30.240Z Has data issue: false hasContentIssue false

Pulsed Laser Etching of GaN and AIN Films

Published online by Cambridge University Press:  10 February 2011

H. Chen
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
R. D. Vispute
Affiliation:
also Materials and Nuclear Engineering, University of Maryland, College Park, MD 20742.
V. Talyansky
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
R. Enck
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
S. B. Ogale
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
T. Dahmas
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
S. Choopun
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
R. P. Sharma
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
T. Venkatesan
Affiliation:
CSR, Department of Physics, University of Maryland, College Park, MD 20742.
A. A. Iliadis
Affiliation:
also Materials and Nuclear Engineering, University of Maryland, College Park, MD 20742.
L. G. Salamanca-Riba
Affiliation:
Department of Electrical Engineering, University of Maryland, College Park, MD 20742.
K. A. Jones
Affiliation:
U.S. Army Research Laboratory, Adelphi, MD 20783.
Get access

Abstract

Due to limited success in wet etching of GaN and AIN, dry etching techniques have become more relevant for the processing of the GaN films. Here we demonstrate the results of an alternative dry etching process, namely, pulsed laser etching, for GaN and AIN. In this method, a KrF pulsed excimer laser (λ=248 nm, τ=30 ns) was used to etch epitaxial GaN and AIN films. The dependence of the etching characteristics on the laser energy density and the number of pulses has been studied. The etch depth showed a linear dependence on the number of pulses over a wide range of laser energy densities. The threshold intensity for GaN etching was determined to be 0.33 J/cm2. The etching rate was found to be a strong function of laser energy density. Above the threshold, the etch rate was found to be 300–1400 Å per pulse leading to etching rates of 0.1–1μm/sec depending upon the laser energy density and the pulse repetition rate. It is shown that the etching mechanism is based on laser induced absorption, decomposition and layer by layer removal of the GaN.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Morkoc, I. H., Strite, S., Gao, G.B., Lin, M.E., Sverdlov, B., and Bums, M., J. Appl. Phys. 76, 1363 (1994), and references therein.10.1063/1.358463Google Scholar
[2] “GaN and Related Materials for Device Applications”, Materials Research Society Bulletin, 22, 1997, and references therein.10.1557/S0883769400032516Google Scholar
[3] Lin, M.E., Fan, Z.F., Ma, Z., Allen, L.H. and Morkoc, H., Appl. Phys. Lett. 64, 887 (1994).10.1063/1.110985Google Scholar
[4] Shul, R.J., McClellan, G.B., Casalnuovo, S.A., Rieger, D.J., Pearton, S.J., Constantine, C., Barratt, C., Karlicek, R.F., Tran, C. and Schurman, M., Appl. Phys. Lett. 69, 1119 (1996).10.1063/1.117077Google Scholar
[5] Ping, A.T., Adesida, I., and Khan, M. Asif, Appl. Phys. Lett. 67, 1250 (1995).10.1063/1.114387Google Scholar
[6] Vartuli, C.B., Pearton, S.J., Lee, J.W., Hong, J., MacKenzie, J.D., Abernathy, C.R. and Shul, R.J., Appl. Phys. Lett. 69, 1426 (1996).Google Scholar
[7] Lee, H., Oberman, D.B. and Harris, J.S., Appl. Phys. Lett. 67, 1754 (1995).Google Scholar
[8] Shul, R.J., Howard, A.J., Pearton, S.J., Abernathy, C.R., Vartuli, C.B., Barnes, P.A. and Bozack, M.J., J. Vac. Sci. Technol. B 13, 2016 (1995).10.1116/1.588126Google Scholar
[9] Inam, A., Wu, X.D., Venkatesan, T., Ogale, S.B., Chang, C.C and Dijkkamp, D., Appl. Phys. Lett. 51,1112 (1987).10.1063/1.98756Google Scholar
[10] Dhote, A.M., Shreekala, R., Patil, S.I., Ogale, S.B., Venkatesan, T. and Williams, C.M., Appl. Phys. Lett. 67, 3644 (1995).10.1063/1.115345Google Scholar
[11] Kelly, M.K., Ambacher, O., Dahlheimer, B., Groos, G., Dimitrov, R., Angerer, H., and Stutzmann, M., Appl. Phys. Lett. 69, 1749 (1996).10.1063/1.117473Google Scholar
[12] Vispute, R.D., Talyansky, V., Sharma, R.P., Choopun, S., Downes, M., Venkatesan, T., Jones, K. A., Iliadis, A.A., Khan, M.A., and Yang, J.W..Google Scholar
[13] Bloom, S., Hardeke, G., Meier, E., and Ortenburger, I.B., Phys. Status Solidi 66, 161 (1974).10.1002/pssb.2220660117Google Scholar
[14] Venkatesan, T., Wu, X.D., Inam, A., and Wachtman, J.B., Appl. Phys. Lett. 52, 1193 (1988).10.1063/1.99673Google Scholar