Generation and annihilation of antiphase domain boundaries in GaAs on Si grown by molecular beam epitaxy

Abstract

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 (001)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.

GaAs/Si epitaxial integration utilizing a two-step, selectively grown Ge intermediate layer

“…First, the epitaxy of polar films on a non-polar substrate results in anti-phase domains (APDs), unless efforts are made to avoid their formation. APDs can be eliminated by using starting substrates with moderate misorientations from the (1 0 0) surface [1][2][3][4][5] or by using specialized growth conditions for on-axis Si(1 0 0) [6]. Second, GaAs has a four percent larger lattice constant than Si.…”

Effect of AlN interlayers in the structure of GaN-on-Si grown by plasma-assisted MBE

“…The heteroepitaxial growth of III-V semiconductors on Si has attracted significant research efforts for more than two decades [1][2][3][4][5][6][7][8][9][10][11]. The most ambitious target of the work on Si(0 0 1) substrates, concerns the monolithic integration of III-V optoelectronic and high frequency electronic devices with Si digital electronic circuits.…”

Growth process and nanostructure of crystalline GaAs on Si(1 1 0) surface prepared by molecular beam epitaxy

“…It is well-known that tilted off Si(1 0 0) substrates with periodic step edges on surface are effective to reduce the lattice defects in the GaAs layer deposited on the Si substrate [2,4,10,11]. A homogeneous coverage is enhanced at the early stage of nucleation of crystalline GaAs because adatoms diffusing on surface preferentially adsorb at the step edge sites and step-flow growth is promoted [12][13][14][15][16].…”