The Effect of  PH 3 Pyrolysis on the Morphology and Growth Rate of InP Grown by Hydride Vapor Phase Epitaxy

Abstract

The incomplete pyrolysis of PH3 is shown to have a significant effect on the growth rate and morphology of InP grown by hydride vapor phase epitaxy. Using ultraviolet absorption spectroscopy to determine the extent of PH~ pyrolysis, the growth rate of InP is shown to increase with decreasing PH~ pyrolysis. Incomplete PH3 pyrolysis is also shown to dramatically increase the formation of growth hillocks on < I00> InP epitaxia] layers. The use of various metal catalysts to expedite PH3 pyrolysis to eliminate hillock formation during InP growth is described, and a qualitative model of PH3 induced hillock growth is presented.

HVPE growth and characterization of GaP on different substrates and patterned templates for frequency conversion devices

“…The temperature dependence of the growth rate indicates that the growth is kinetically rather than thermodynamically limited similar to other findings [28,29]. The difference between these 2 regimes is that while in a kinetically limited process events at a molecular level like removal of the chemisorbed chlorine as HCl play ratelimiting role [30], in a mass limited process factors like mass flow rate and, actually, what portion of the flow reacts with the substrate [29] will have more pronounced impact than the temperature. Similar conclusion, that HVPE (in case of GaAs) is mainly governed by surface kinetics, can be also found in [31].…”

“…(1) the reduction of parasitic deposits in the process; (2) obtaining the appropriate balance between absorption of Ga (GaCl) and P (PH 3 ) precursors and desorption of HCl thereby, reducing competition between P and Cl for available surface sites [29,30]; (3) the appropriate balance between PH 3 , and the generated during the pyrolysis P 2 + and P 4 2+ [28].…”

“…PH 3 has a higher equilibrium constant in the reaction with GaCl in comparison to the other two species and plays the main role in desorption of chlorine from the layer surface. By decomposing on the growing surface, PH 3 supplies the chlorine which is already chemisorbed in the layer with atomic hydrogen more rapidly than the supply that could possibly come from dissociation of molecular hydrogen [30]. This increase of the growth rate at uncompleted PH 3 pyrolysis can be, however, at the expense of the surface morphology.…”

“…Thus, the un-reacted gallium can condense as droplets on the layer surface. Further, the Ga-droplets can initiate forming of hill- ocks via vapor-liquid-solid growth [30]. The choice of appropriate combination of the process parameters like substrate and Ga temperature, reactor pressure [35,36], and supersaturation facilitated the above mentioned mechanisms and allowed to achieve growth rates as high as 93 µm/h on unpatterned templates.…”

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

“…As a result, the intermediate in the The initial lateral growth defined as the growth away from the mesa wall at half the height of the mesa in the very first minute is presented in the form of Arrhenius plots in Fig. 5 The decrease in growth rate with the increase of temperature is due to an enhanced pyrolysis of PH3 to P2 which is knot+n to reduce the g r o~t h rate [11][12] These curves also confirm that the growth is always more abundant in the [i 101 mesa at all the investigated temperatures in accordance with the dangling bond arguments and the Cadoret model discussed in the previous paragraphs. A similar trend has also been observed for the case where the regrowth was carried out with-out mask [ 3 ] .…”