Ag-assisted CBE growth of ordered InSb nanowire arrays

We present growth studies of InSb nanowires grown directly on InSb(111)B and InAs(111)B substrates. The nanowires were synthesized in a chemical beam epitaxy (CBE) system and are of cubic zinc blende structure. To initiate nanowire nucleation we used lithographically positioned silver (Ag) seed particles. Up to 87% of the nanowires nucleate at the lithographically pre-defined positions. Transmission electron microscopy (TEM) investigations furthermore showed that, typically, a parasitic InSb thin film forms on the substrates. This thin film is more pronounced for InSb(111)B substrates than for InAs(111)B substrates, where it is completely absent at low growth temperatures. Thus, using InAs(111)B substrates and growth temperatures below 360 degrees C free-standing InSb nanowires can be synthesized.