GaAs epitaxial layers with low electron concentrations were obtained from an alkylgallium and arsine system by use of triethylgallium. The highest Hall mobihty of the layer, with an electron concentration of 7.0 • 1013/cm8 at 77~ was 120,000 cmz/V sec. Carrier concentration and carrier type of the layer could be changed in the range of from 1012 to ,~ 1016/cm 3 by changing the arsine to triethyl gallium mole ratio introduced into a deposition zone. This fact was expected to be due to the amphoteric impurity sharing between the arsenic and the gallium sites of GaAs crystal.Although the extension of carrier concentration to the lower range resulted from impurity compensation, mobility data of the layers of electron concentrations higher than about 1014/cm 3 were almost the same as those from the usual AsCJ~-Ga-H2 system. Dominant acceptor impurities observed in the photolummescence measurements were discussed and were correlated with amphoteric silicon and carbon impurities. This was consistent with the result obtained on the ~npurities of the layer by mass spectroscopic analysis.One of the most commonly used techniques for growing high purity GaAs epitaxial layers from vapor phase is one using the AsC18-Ga-H2 system (1). Because of extensive efforts for growing high purity GaAs over the past several years (2-8), it is now possible to obtain GaAs with total ionized impurity concentration (ND -~-NA) in the 1013/cm s range (4). Although recent reports throw light on the preparation of high purity GaAs (5-8), the AsC13-Ga-H2 system is rather complicated and somewhat unstable (9).A system using alkylgallium and arsine, first reported by Manasevit (10), seems to have some advantage compared with the AsC18-Ga-H2 system. This system required only one temperature zone, whose temperature is easily controlled inductively by r.f. power. Crystal growth takes place on the substrate on a heated pedestal in a quartz tube with a cool wall. The system does not contain reactive halogen. This seems to be an important factor to suppress impurity incorporation into the layer from the reactor system.In spite of extensive experiments on the deposition of the layer by this method (11-15), total impurity (ND-~-NA) seems to be higher than 1016/cm ~ so far.Rai-Chaudhury (12) and Ito et aI. (15) detected a large quantity of impurities in the layer, such as silicon, carbon, and others by the mass spectroscopic analysis. Shallow active impurities of the layer were examined by the photoluminescence measurement and were expected to be carbon and/or silicon which mainly come from the trimethylgallium source (15). These reports seemed to show that a high purity gallium source, whose silicon and carbon impurities are reduced, should be used to obtain a high purity GaAs layer. Lindeke et al. (16) used distilled gallium diethyl chloride as gallium source, but the electron Hall mobility data at 77~ showed that impurity concentration was nearly the same as that from the trimethylgallium source.In this experiment, high purity triethylga]lium (TEG) was us...
Epitaktische GaAs‐Schichten mit geringer Elektronenkonzentration werden aus Triäthylgallium und AsH3 erhalten.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.