TI DOPING OF INP AND GAINAS USING TICL4

TiCl4 is a very efficient source of Ti doping for InP grown by low pre ssure organometallic vapor phase epitaxy (OMVPE), and we report some c haracteristics of the doping behavior. Precipitates are visible in the material (TEM observation) for Ti concentrations > 10(18) cm(-3), alt hough morphological problems only appear for concentrations above 10(1 9) cm(-3). As reported by other authors, a delay in incorporation is s een, and attributed to the reaction of TiCl4 with oxygen or oxygen-con taining compounds adsorbed on the reactor walls. Also as reported befo re, we find that the level of electrical activity of Ti in InP stays l ow, although it is sufficient to allow the growth of semi-insulating I nP:Zn + Ti or InP:Fe + Ti. TiCl4 does not introduce Ti in AIInAs, but Ti doping of GaInAs is obtained, and can render the material highly re sistive. The incorporation of Zn is seen to be influenced (slightly in creased) by the introduction of Ti.