Temporally resolved selective regrowth of InP around [110] and [1¯10] directional mesas

A near equilibrium process, hydride vapour phase epitaxy (HVPE) has been used to study the selective growth of InP around the RIE (reactive ion etching) [110] and [1¯10] mesas. The regrown patterns are strikingly different for the two types of mesas considered. The lateral growth is higher in the case of the [1¯10] oriented mesas at all the studied temperatures and is understood to be due to a more favourable net change of dangling bonds. The initial lateral growth defined as the growth away from the mesa at half the height of the mesa in the very first minute is a decreasing function of temperature and is interpreted to be due to an enhanced pyrolysis of phosphine. An immense lateral growth has to be considered when a particular amount of dopant has to be incorporated very near the mesa. This has been exemplified by considering Fe incorporation when InP:Fe is regrown for buried heterostructure laser fabrication