Generation and annihilation of antiphase domain boundaries in GaAs on Si grown by molecular beam epitaxy
- PDF / 2,303,535 Bytes
- 14 Pages / 576 x 792 pts Page_size
- 91 Downloads / 225 Views
J. Stoemenos Physics Department, Aristotle University of Thessaloniki, 540 06 Thessaloniki, Greece
K. Tsagaraki Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), P.O. Box 1527, 711 10 Heraklion, Crete, Greece
Ph. Komninou and N. Flevaris Physics Department, Aristotle University of Thessaloniki, 540 06 Thessaloniki, Greece
P. Panayotatos Department of Electrical and Computer Engineering, Rutgers University, P.O. Box 909, Piscataway, New Jersey 08855-0909 and Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH), P.O. Box 1527, 711 10 Heraklion, Crete, Greece
A. Christou CALCE Electronic Packaging Research Center, Microelectronics Devices Laboratory, University of Maryland, College Park, Maryland 20742 (Received 9 January 1992; accepted 26 March 1993)
A comprehensive investigation of antiphase domain boundaries (APB's) in GaAs-on-Si is presented. A comprehensive experimental approach, based on complementary electron microscopy (TEM and SEM) and chemical etch techniques, is developed and used in the study of the structural evolution of APB's on vicinal (OOl)Si substrates. The question of whether a GaAs selective nucleation or APB annihilation accounts for the absence of APB's in thick GaAs/Si films, grown on substrates misoriented from (001) toward (110), is addressed. APB's are revealed by two different TEM techniques to exist in the first interfacial layers of GaAs/Si even in samples considered to be "APB free". The APB annihilation mechanism is illustrated in GaAs films grown on substrates misoriented toward (100), either directly, by cross-sectional TEM observations, or indirectly, by combined chemical etch/SEM experiments. In addition, the structural characteristics of APB's and their interaction with other extended crystal defects are clarified by XTEM and TEM observations. Finally, the influence of APB's on GaAs/Si surface morphology and their electrical activity are shown explicitly for the first time.
I. INTRODUCTION Research in the growth of III-V semiconductors on Si has attracted much attention in the last five years.1"3 Gallium arsenide on Si is the most frequently investigated system, and significant progress has been already realized.4 However, various aspects of GaAs on Si heteroepitaxy, such as the antiphase domains (APD's) problem and the occupation of the two GaAs/Si sublattices,5~7 remain to be clarified. The above two issues arise from the polar on nonpolar nature of the GaAs-on-Si heteroepitaxy. When the occupation of the two sublattices in the zinc blende structure does not remain the same in the entire crystal, then antiphase domains (APD's) are formed which are separated by antiphase domain boundaries (APB's) (Fig. 1). The wrong 1908
http://journals.cambridge.org
J. Mater. Res., Vol. 8, No. 8, Aug 1993
Downloaded: 27 Aug 2015
bonds across an APB connect like atoms and have a higher energy than the right bonds that connect unlike atoms. Hence, the existence of APB's is energetically unfavora
Data Loading...
