A new growth method to make highly oriented GaAs thin films on flexible metal substrates has been developed, enabling roll-to-roll manufacturing of flexible semiconductor devices. The grains are oriented in the <001> direction with <1 degree misorientations between them, and they have a comparable mobility to single-crystalline GaAs at high doping concentrations. At the moment, the role of low-angle grain boundaries (LAGBs) on device performance is unknown. A series of electron backscatter diffraction (EBSD) and cathodoluminesence (CL) studies reveal that increased doping concentrations decrease the grain size and increase the LAGB misorientation. Cross-sectional scanning transmission electron microscopy (STEM) reveals the complex dislocation structures within LAGBs. Most importantly, a correlative EBSD/electron beam-induced current (EBIC) experiment reveals that LAGBs are carrier recombination centers and that the magnitude of recombination is dependent on the degree of misorientation. The presented results directly link increased LAGB misorientation to degraded device performance, and therefore, strategies to reduce LAGB misorientations and densities would improve highly oriented semiconductor devices.
Poplawsky, Jonathan D., et al. "Directly Linking Low-Angle Grain Boundary Misorientation to Device Functionality for GaAs Grown on Flexible Metal Substrates." ACS Applied Materials and Interfaces, vol. 12, no. 9, Feb. 2020. https://doi.org/10.1021/acsami.9b22124
Poplawsky, Jonathan D., Dutta, Pavel, Guthrey, Harvey, et al., "Directly Linking Low-Angle Grain Boundary Misorientation to Device Functionality for GaAs Grown on Flexible Metal Substrates," ACS Applied Materials and Interfaces 12, no. 9 (2020), https://doi.org/10.1021/acsami.9b22124
@article{osti_1602698,
author = {Poplawsky, Jonathan D. and Dutta, Pavel and Guthrey, Harvey and Leonard, Donovan and Guo, Wei and Kacharia, Mitsul and Rathi, Monika and Khatiwada, Devendra and Favela, Carlos and Sun, Sicong and others},
title = {Directly Linking Low-Angle Grain Boundary Misorientation to Device Functionality for GaAs Grown on Flexible Metal Substrates},
annote = {A new growth method to make highly oriented GaAs thin films on flexible metal substrates has been developed, enabling roll-to-roll manufacturing of flexible semiconductor devices. The grains are oriented in the direction with <1 degree misorientations between them, and they have a comparable mobility to single-crystalline GaAs at high doping concentrations. At the moment, the role of low-angle grain boundaries (LAGBs) on device performance is unknown. A series of electron backscatter diffraction (EBSD) and cathodoluminesence (CL) studies reveal that increased doping concentrations decrease the grain size and increase the LAGB misorientation. Cross-sectional scanning transmission electron microscopy (STEM) reveals the complex dislocation structures within LAGBs. Most importantly, a correlative EBSD/electron beam-induced current (EBIC) experiment reveals that LAGBs are carrier recombination centers and that the magnitude of recombination is dependent on the degree of misorientation. The presented results directly link increased LAGB misorientation to degraded device performance, and therefore, strategies to reduce LAGB misorientations and densities would improve highly oriented semiconductor devices.},
doi = {10.1021/acsami.9b22124},
url = {https://www.osti.gov/biblio/1602698},
journal = {ACS Applied Materials and Interfaces},
issn = {ISSN 1944-8244},
number = {9},
volume = {12},
place = {United States},
publisher = {American Chemical Society (ACS)},
year = {2020},
month = {02}}
Ziegler, James F.; Ziegler, M. D.; Biersack, J. P.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol. 268, Issue 11-12https://doi.org/10.1016/j.nimb.2010.02.091