COOLING RATE DETERMINATION OF SI SAMPLES IN A RADIATIVE QUENCH AND OBSERVATION OF AN APPARENT TEMPERATURE SHIFT OF THE 1X1-7X7 SURFACE PHASE-TRANSITION
Ma. Kulakov et al., COOLING RATE DETERMINATION OF SI SAMPLES IN A RADIATIVE QUENCH AND OBSERVATION OF AN APPARENT TEMPERATURE SHIFT OF THE 1X1-7X7 SURFACE PHASE-TRANSITION, Surface science, 376(1-3), 1997, pp. 414-418
A simple method of cooling rate determination of Si samples in a radia
tive quench is presented. The method relies on monitoring of the LEED
pattern of the Si(111) sample during quench and exact determination of
the onset of the 1x1-7x7 phase transition using a videorecord of the
process. The temperature decrease is found to be essentially linear an
d the cooling rate is constant over the temperature range 1275-840 deg
rees C. In different experiments this rate was about 300, 500 and 1000
degrees C/s for 0.4, 0.2 and 0.085 mm thick samples, respectively. An
apparent temperature shift of the 1x1-7x7 phase transition upon quenc
hing is observed for the first time. Slow relaxation of surface adatom
concentration is assumed to be responsible for this shift. (C) 1997 E
lsevier Science B.V.