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Robertson, Ian M. Turkot, Britt Anne 2011-05-07T12:51:04Z 2011-05-07T12:51:04Z 10000-01-01 1996 The implantation damage behavior of GaAs/Al$\sb{0.6}$Ga$\sb{0.4}$As multilayer structures has been investigated by implanting samples with 1 MeV Kr$\sp+$, 1.5 MeV Kr$\sp+$, 1 MeV Ar$\sp+$, and 1.5 MeV Kr$\sp{++}$ at 77 K. The resulting damage state was analyzed using low-, room-, and high-temperature Rutherford backscattering spectrometry ion channeling and room-temperature transmission electron microscopy techniques. In all implantations the level of damage produced in these structures was found to increase with depth, and the damage state produced in samples containing single- and double-layers of $\rm Al\sb{0.6}Ga\sb{0.4}As$ was independent of the internal interfaces. The observed damage can be explained using a model which relates the amount of implantation-induced disorder to the number of cascade-producing events in a given region. This model can also account for results in the GaAs/AlAs system, such as the greater amount of mixing which is observed to occur at deeper AlAs interfaces and also that amorphization of AlAs layers initiates at the interfaces. Room temperature recovery of partially crystalline $\rm Al\sb{0.6}Ga\sb{0.4}As$ was observed to occur following low temperature implantation. Depending on the implantation condition, this room temperature recovery can lead to the development of planar defects. In addition, the extent of recovery in $\rm Al\sb{0.6}Ga\sb{0.4}As$ was found to be related to the original damage state, with more complex damage requiring higher annealing temperatures. Misoriented crystallites were produced by the recrystallization of GaAs implanted at room temperature to a dose far exceeding that required for low temperature amorphization. Continued ion impacts produced crystalline nucler which increased in size as a result of the enhanced atomic motion produced by the energetic ions. Similar crystallites were found in TEM foils which remained in the as-thinned condition for several months. In these samples, recrystallization resulted from a mechanism involving low energy events with the ability to induce bond rearrangement. Made available in DSpace on 2011-05-07T12:51:04Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9702693.pdf: 6164703 bytes, checksum: 7c45874bd6aef148d2df2e27bdfc4c83 (MD5) Previous issue date: 1996 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:46:42Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:20:57-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only 9780591089677 AAI9702693 (UMI)AAI9702693 http://hdl.handle.net/2142/20847 eng Copyright 1996 Turkot, Britt Anne Engineering, Electronics and Electrical Engineering, Materials Science Investigation of implantation damage in aluminum gallium arsenide/gallium arsenide heterostructures using ion channeling and transmission electron microscopy text Materials Science and Engineering Materials Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.