Project Report

This project attempted the fabrication of patterned silicon films on transparent materials such as quartz using a process known as aluminum induced crystallization (AIC). In this process, a crystalline aluminum and non-crystalline silicon layer are deposited on the quartz surface and then heated. The layers exchange places and the silicon layer crystallizes, forming a crystalline silicon thin film on quartz (Figure 1). The AIC process has a pair of unique features that provided the central motivation for this project. Firstly, using AIC allows for control of the final crystal orientation of the silicon film, important since many silicon thin film applications require a specific surface orientation. Secondly, a recent report proposed that if the Al and Si layers are less than 50nm thick, silicon crystallization would start at the aluminum/quartz interface instead of the aluminum/silicon interface. This suggests that by patterning quartz, a patterned silicon thin film can be made using AIC For these experiments, samples were prepared at both Penn State University and Kyushu University. Experiments were performed at Kyushu University using samples with 25-100µm square and line patterns. Additional experiments were also performed at Tohoku University, using an in-situ microscopy system to observe the AIC process in real time. Several promising results were obtained from these experiments. In-situ observations of AIC on the patterned samples showed that silicon crystallization rates were faster in patterned regions than unpatterned regions. As heating temperatures decreased, the differences in crystallization rates became more pronounced, and films with crystallized silicon exclusively in the patterned regions were able to be formed. The positive experimental results were not the only benefit of this project. The project has the potential to foster the development of a new collaboration between Penn State University and both Kyushu University and Tohoku University researchers, as the research interests of all three groups overlap. Based on the results of these experiments, an abstract has been submitted to the Spring MRS 2012 Research symposium. Furthermore, these experiments have been continued at Penn State since the end of the EAPSI program. While there are many challenges that must be addressed, the initial results suggest that this experiment could be continued well into the future.

Agency
National Science Foundation (NSF)
Institute
Office of International and Integrative Activities (IIA)
Application #
1108047
Program Officer
Carter Kimsey
Project Start
Project End
Budget Start
2011-06-01
Budget End
2012-05-31
Support Year
Fiscal Year
2011
Total Cost
$5,920
Indirect Cost
Name
Hainey Mel F
Department
Type
DUNS #
City
State College
State
PA
Country
United States
Zip Code
16801