Tetrakistrifluorophosphine platinum: Investigations into its chemical vapor deposition chemistry

This study examined the chemical vapor deposition (CVD) chemistry of Pt(PF{dollar}sb3)sb4{dollar}, specifically, the chemical reactions at the substrate surface as well as the secondary chemistry that occurred away from the deposition area. Many of the films contained a phosphorus impurity that was determined to be PtP{dollar}sb2{dollar} through x-ray diffraction and thermogravimetric analysis. A hot wall CVD system was used to investigate the effect of several deposition variables. The phosphorus content of the dissolved film was measured with phosphorus nuclear magnetic resonance spectrometry and product gases were analyzed with Fourier transform infrared spectroscopy (FT-IR). The decomposition of Pt(PF{dollar}sb3)sb4{dollar} took place clearly to produce pure platinum films when evolved PF{dollar}sb3{dollar} gas was quickly removed and not given time to react with surrounding surfaces. This occurred under high vacuum conditions. Given time, PF{dollar}sb3{dollar} reacted with the freshly deposited platinum surface, resulting in phosphorus contamination. The reaction of PF{dollar}sb3{dollar} with Pt was responsible for the production of PtP{dollar}sb2{dollar} solid and PF{dollar}sb5{dollar} gas. Depositions carried out in glass led to additional reactions. The PF{dollar}sb3{dollar} gas reacted with SiO{dollar}sb2{dollar} to produce SiF{dollar}sb4{dollar} gas and P{dollar}sb4{dollar}O{dollar}sb6{dollar} liquid. The PF{dollar}sb5{dollar} gas reacted with SiO{dollar}sb2{dollar} to form POF{dollar}sb3{dollar} and SiF{dollar}sb4{dollar} gases. These reactions were not observed when copper tubing was used. Phosphorus contamination levels were lowered through post-treatment, specifically with oxygen gas. A longer post-treatment time at the deposition temperature resulted in purer films, which indicated that the kinetics of oxidation were slow.; Electron spectroscopy for chemical analysis (ESCA) was used to analyze films produced with the cold wall CVD system. This technique showed that fluorine was absent, so simple entrapment of PF{dollar}sb{lcub}rm x{rcub}{dollar} (x = 1-3) species was ruled out as a contributor to the film contamination.; The purified Pt(PF{dollar}sb3)sb4{dollar} liquid source was examined with FT-IR spectroscopy, Fourier transform ion-cyclotron resonance mass spectrometry (FT-ICR MS), and platinum nuclear magnetic resonance spectrometry, and by other tests to identify impurities. No significant quantities of impurity were observed.; A yellow crystalline compound was observed to form during hot wall depositions. Its formula was determined to be Pt{dollar}sb4{dollar}(PF{dollar}sb3)sb8{dollar} using FT-ICR MS and further study showed that it did not contribute to the film contamination.