Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-19T09:58:07.907Z Has data issue: false hasContentIssue false

Pulsed–light Crystallization of Thin Film Silicon, Germanium, and Silicon Germanium Alloy

Published online by Cambridge University Press:  07 July 2014

Baojie Yan
Affiliation:
Wintek Electro-Optics Corporation, Ann Arbor, Michigan
William Toner
Affiliation:
Wintek Electro-Optics Corporation, Ann Arbor, Michigan
Mukul Dubey
Affiliation:
Department of Electrical Engineering and Computer Science, South Dakota State University, Brookings, South Dakoda
Qihua Fan
Affiliation:
Department of Electrical Engineering and Computer Science, South Dakota State University, Brookings, South Dakoda
Chun-Sheng Jiang
Affiliation:
National Renewable Energy Laboratory, Golden, Colorado
David Stevenson
Affiliation:
Wintek Electro-Optics Corporation, Ann Arbor, Michigan
Get access

Abstract

We report the recent progress of crystallization of amorphous silicon (a-Si), amorphous germanium (a-Ge) and amorphous silicon germanium alloy (a-SiGe) using a pulsed-Xenon-lamp system with multiple lamps. The precursor materials were deposited using a sputtering machine on display glass substrates maintained on a rotary holder. The RF powers on the silicon and germanium targets were varied to control the Ge/Si ratio in the materials. The film thickness was in the range of 50-100 nm, targeting the application in thin film transistors (TFT). The samples were pre-heated to 350-450°C in a conveyer chamber with nitrogen flow before the crystallization. The materials were characterized using AFM, Raman and Spectroscopic Ellipsometry. We demonstrated that we can uniformly crystallize a-Si, a-SiGe, and a-Ge with a single-pulse or multiple-pulse process on 10×5 cm2 glass substrates. We found that the required crystallization power for a-Ge is much lower than for a-Si. The power needed to crystallize a-SiGe is between the power required for a-Ge and a-Si crystallizations, and it increased with increasing Si fraction. No Raman signal was measurable in the as-deposited films. Strong Raman peaks at 520 cm-1 and 290 cm-1 were observed in the pulsed-lamp crystallized poly-Si and poly-Ge films, respectively. Distinct Ge-Ge, Si-Ge, and Si-Si vibration modes were observed at ~285 cm-1, ~390 cm-1, and ~470 cm-1, respectively, in the poly-SiGe films formed after the pulsed-light treatments. Their intensity ratios and the peak positions depended on the Ge/Si ratio and the light intensity used for the crystallization. AFM images showed the formation of large grains with increased surface roughness.

Type
Articles
Copyright
Copyright © Materials Research Society 2014 

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

Thin-Film Silicon Solar Cells, edited by Shah, A., EPFL Press, 2010, Lausanne, Switzerland.CrossRefGoogle Scholar
Guha, S., Yang, J., and Yan, B., Solar Energy Materials & Solar Cells, 119, 1 (2013).CrossRefGoogle Scholar
Haschke, J., Jogschies, L., Amkreutz, D., Korte, L., and Rech, B., Solar Energy Materials & Solar Cells, 115, 7 (2013).CrossRefGoogle Scholar
Varlamova, S., Dore, J., Evans, R., et al. ., Solar Energy Materials & Solar Cells, 119, 246 (2013).CrossRefGoogle Scholar
Xu, L. and Grigoropoulosa, C. P., J. Appl. Phys. 99, 034508 (2006).CrossRefGoogle Scholar
Pier, T., Kandoussi, K., Simon, C., Coulon, N., Lhermite, H., Mohammed-Brahim, T., Bergamini, J. F., Thin Solid Films 515, 7585 (2007).CrossRefGoogle Scholar
Maioloa, L., Pecoraa, A., Maitaa, F., et al. ., Sensors and Actuators B 179 114 (2013).CrossRefGoogle Scholar
Wang, C.-L., Lee, I-C., Wu, C.-Y., Cheng, Y.-T., Yang, P.-Y., Cheng, H.-C., Thin Solid Films 529, 421 (2013).CrossRefGoogle Scholar
Ohdaira, K., Tomura, N., Ishii, S., and Matsumura, H., Thin Solid Films 519, 4459 (2011)Google Scholar
Nishikawa, T., Ohdaira, K., and Matsumura, H., Current Appl. Phys. 11 604 (2011).CrossRefGoogle Scholar
Ohdaira, K. and Matsumura, H., Cryst, J.. Growth, 362, 149 (2013).Google Scholar
Subramanian, V. and Saraswat, K. C., IEEE Tran. Electron Devices. 45, 1690 (1998).Google Scholar
Jin, Z., Kwok, H. S., and Wong, M., IEEE Tran. Electron Devices Lett. 19, 502 (1998).Google Scholar
Perova, T. S., Wasyluk, J., Lyutovich, K., Kasper, E., Oehme, M., Rode, K., and Waldron, A., J. Appl. Phys. 109, 033502 (2011).CrossRefGoogle Scholar
Pages, O., Hussein, R. H., and Torres, V. J. B., J. Appl. Phys. 114, 033513 (2013).CrossRefGoogle Scholar