ABSTRACT
Self-limiting epitaxial growth [13]is one of the most promising epitaxial technology for the fabrication of ultra thin-layered structures with atomic accuracy. In ALE using MOCVD reactors, [4] in which the growth pressure is around 10 Torr, there have been few reports on self-limiting growth of InP using alternate injection of TMI and TBP [5]. Furthermore, in InP growth with a growth pressure in UHV chamber, self-limiting growth has not been reported. [6] Self-limiting growth in UHV is attractive method for achieving small gas consumption, accurate analysis of surface reactions, [7] and combination with digital etching [8]. We have reported on digital etching of a (001) InP substrate using intermittent injections of trisdimethylphosphorus (TDMAP) [9,10] or TBP [11,12] at etching temperatures below 350°C in UHV without any external trigger as a surface-cleaning method. TDMAP [13] and TBP [14] are attractive alternatives to phosphine (PH3) [15,16] because of their low toxicity and low pyrolysis temperature. Therefore, by the combination of self-limiting growth and digital etching prior to the growth in the same chamber, low-temperature processes for a clean interface and also for regrowth on nanostructures have been expected in UHV.
