Ion—molecule reactions in GeH 4/SiH 4 systems studied by ion trap mass spectrometry

Abstract

Gas phase ion—molecule reactions occurring in GeH 4/SiH 4 systems under different partial pressures and their mechanisms have been investigated by ion trap mass spectrometry (ITMS). SiH + n ( n=0–3) and GeH + n ( n = 0–3) are the main ionic species at zero reaction time when the GeH 4: SiH 4 ratio is in the range 1:1 to 1:12. Self-condensation sequences are observed at increasing reaction times. Moreover, formation of ions containing GeSi bonds, such as GeSiH + n ( in = 2–5) and GeSi 2H + n ( n = 4, 5), occurs by reactions of Si 2H + n ( n = 2–5) and Si 3H + n ( n = 4, 5) with GeH 4. At longer reaction times, further substitution of silicon with germanium in GeSiH + n ( n = 2–5) ions has been observed, to give Ge 2H + n ( n = 2–5).