Growth mode and structural characterization of GaSb on Si (001) substrate: A transmission electron microscopy study

Abstract

Growth mode and structural properties of GaSb layers grown on silicon substrate by molecular beam epitaxy method are investigated by transmission electron microscopy. It is found that the GaSb grows to three-dimensional islands and grains are tilted to reduce a lattice mismatch through twin boundaries when they are directly grown on Si substrate. A low-temperature (LT) AlSb buffer plays a key role in transferring the growth mode from a three-dimensional island to a layer-by-layer structure. When the LT AlSb layer is used as a buffer, 90° misfit dislocations, with the Burgers vector b of 1∕2a⟨110⟩, are observed on the interface.

Atomistic modeling of strain distribution in self-assembled interfacial misfit dislocation (IMF) arrays in highly mismatched III–V semiconductor materials

“…The IMF arrays have been reported in several systems including GaP/Si [9], GaAs/Si [10], InAs/GaAs [11], InAs/ GaP [12], GaSb/GaAs [14][15][16][17][18], InP/GaAs [21] and AlSb/Si [22,23] over a range of lattice-mismatched conditions ranging from Da o /a o ¼ 0.4% (GaP/Si) to Da o /a o $13% (AlSb/Si). To date, the IMF formation process has not been well established in the literature.…”

“…The latter approach involving IMF formation appears fundamentally different from the metamorphic approach as strain energy is immediately relieved at the interface by laterally propagating (901) misfit dislocations confined to the epi-substrate interface [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. After IMF array formation, subsequent material deposition proceeds in a strainfree layer-by-layer growth mode.…”

“…In particular, lattice-mismatched epitaxy of Sb-based materials on GaAs and Si substrates are attractive for advanced optoelectronic devices including monolithically integrated lasers [1,2], detectors [3,4], solar cells [5,6] and transistors [7,8]. Two prominent approaches to mismatched epitaxy involve either thick monolithic buffer layers or interfacial misfit dislocation (IMF) arrays [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. The former growth technique involves tetragonal distortion within a critical thickness followed by misfit dislocation and often threading dislocations to alleviate strain in the bulk material [24].…”

Comprehensive investigation of the interfacial misfit array formation in GaSb/GaAs material system

“…Since then the IMF has been implemented in several systems including GaP/Si [11], GaAs/Si [12], InAs/GaAs [13], InAs/GaP [14], InP/GaAs [15], AlSb/Si [16] and GaAs on GaSb [17]. However, so far this mode has not been well-established due to both unrepeatable growth under technological conditions in a narrow epitaxial window and complex characterization.…”

Growth and characterization of GaSb/AlGaSb multi-quantum well structures on Si (001) substrates

“…For the past few years, epitaxial growth and characterization of GaSb layers on Si have been reported by several workers [6][7][8]. Akahane et al [9][10][11] reported the heteroepitaxial growth of GaSb films on Si substrates by introducing an AlSb initiation layer.…”