Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-15T05:39:49.215Z Has data issue: false hasContentIssue false

Effect of Growth Pressure and Gas-Phase Chemistry on the Optical Quality of InGaN/GaN Multi-Quantum Wells

Published online by Cambridge University Press:  05 April 2013

E.A. Armour
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
D. Byrnes
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
R.A. Arif
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
S.M. Lee
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
E.A. Berkman
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
G.D. Papasouliotis
Affiliation:
Veeco Instruments, Turbodisc Operations, 394 Elizabeth Avenue, Somerset, NJ 08873, U.S.A.
C. Li
Affiliation:
Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A.
E.B. Stokes
Affiliation:
Department of Electrical and Computer Engineering, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A. Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A.
R. Hefti
Affiliation:
Nanoscale Science Program, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A.
P. Moyer
Affiliation:
Department of Physics & Optical Science, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A. Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC 28223, U.S.A.
Get access

Abstract

Blue light-emitting diodes (LED's), utilizing InGaN-based multi-quantum well (MQW) active regions deposited by organometallic chemical vapor epitaxy (OMVPE), are one of the fundamental building-blocks for current solid-state lighting applications. Studies [1,2] have previously been conducted to explore the optical and physical properties of the active MQW's over a variety of different OMVPE growth conditions. However, the conclusions of these papers have often been contradictory, possibly due to a limited data set or lack of understanding of the fundamental fluid dynamics and gas-phase chemistry that occurs during the deposition process.

Multi-quantum well structures grown over a range of pressures from typical low-pressure production processes at 200 Torr, up to near-atmospheric growth conditions at 700 Torr, have been investigated in this study. At all growth pressures, clear trends of gas-phase chemical reactions are observed for increased gas residence times (lower gas speeds from the injector flange and lower rotation rates) and increased V/III ratios (higher NH3 flows).

Confocal microscopy, excitation-dependent PL (PLE), and time-resolved photo-luminescence (TRPL) have been employed on these MQW structures to investigate the carrier lifetime characteristics. Confocal emission images show spatially-separated bright and dark regions. The bright regions are red-shifted in wavelength relative to the dark regions, suggesting microscopic spatial localization of high indium content regions. As the growth pressure and gas residence times are reduced, a larger difference in band-gap between bright and dark regions, longer lifetimes, and higher average PL intensities can be obtained, indicating that higher optical quality material can be realized. Optimized MQW's grown at high pressure exhibit higher PLE slope intensities and IQE characteristics than lower pressure samples. Results on simple LED structures indicate that the improvement in MQW optical quality at high pressures translates to higher output power at a 110 A/cm2 injection current density.

Type
Articles
Copyright
Copyright © Materials Research Society 2013 

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

REFERENCES

Oliver, R.A., Kappers, M. J., Humphreys, C.J., and Briggs, G.A.D., J. Appl. Phys. 97, 013707 (2005).CrossRefGoogle Scholar
Lundin, W.V., Zavarin, E.E., Sinitsyn, M.A., Sakharov, A.V., Usov, S.O., Nikolaev, A.E., Davydov, D.V., Cherkashin, N.A., and Tsatsulnikov, A.F., Fiz. Tekh. Poluprovodnikov 44, 126, (2010) [Semiconductors 44, 123(2010)].Google Scholar
Creighton, J.R., Wang, G.T., Breiland, W.G., and Coltrin, M.E., J. Crystal Growth 261, 204 (2004).CrossRefGoogle Scholar
Creighton, J.R., Coltrin, M.E., and Figiel, J.J., Appl. Phys. Lett. 93, 171906 (2008).CrossRefGoogle Scholar
Stringfellow, G.B., J. Crystal Growth 312, 735 (2010).CrossRefGoogle Scholar
Demchuk, A., Porter, J., and Koplitz, B., J. Phys. Chem. A 102, 8841 (1998).CrossRefGoogle Scholar
Mitrovic, B., Gurary, A., and Kadinski, L., J. Crystal Growth 287, 656 (2006).CrossRefGoogle Scholar
Lee, S.R., West, A.M., Allerman, A.A., Waldrip, K.E., Follstaedt, D.M., Provencio, P.P., Koleske, D.D., and Abernathy, C.R., Appl. Phys. Lett. 86, 241904 (2005).CrossRefGoogle Scholar
Armour, E.A., Mitrovic, B., Zhang, A., Ebert, C., Pophristic, M., and Paranjpe, A. in Compound Semiconductors for Generating, Emitting and Manipulating Energy, edited by Li, T., Mastro, M., Dadgar, A., Jiang, H., and Kim, J., (Mater. Res. Soc. Symp. Proc. 1396, Boston, MA, 2011) pp. 314.Google Scholar
Manasson, Alexander, private internal Veeco communication (2013).Google Scholar
Na, J.H., Lee, S.K., Lim, H.S., Kwon, H.K., Son, S., and Oh, M.S., presented at the 16th International Conference on Metal Organic Vapor Phase Epitaxy, Busan, Korea, 2012 (unpublished).Google Scholar