The Use of Metalorganics in the Preparation of Semiconductor Materials: VIII . Feasibility Studies of the Growth of Group III ‐Group V Compounds of Boron by MOCVD

Abstract

Boron‐arsenic and boron‐phosphorus films have been grown on Si, sapphire, and silicon‐on‐sapphire (SOS) by pyrolyzing Group III alkyls of boron, i.e., trimethylborane (TMB) and triethylborane (TEB), in the presence of and , respectively, in a atmosphere. No evidence for reaction between the alkyls and the hydrides on mixing at room temperature was found. The films were predominantly amorphous. The film growth rate was found to depend on the concentration of alkyl boron compound and was essentially constant when TEB and were pyrolyzed over the temperature range 550°–900°C. The films were found to contain mainly carbon impurities (the amount varying with growth temperature), some oxygen, and were highly stressed and bowed on Si substrates, with some crazing evident in thin (2 μm) B‐P and thick (5 μm) B‐As films. The carbon level was generally higher in films grown using TEB as the boron source. Films grown from and TMB showed a higher carbon content than those grown from and TMB. Based on their B/As and B/P ratios, films with nominal compositions and were grown using TMB as the boron source.