The temperature dependences of the ion-induced electron emission yield c of highly-oriented pyrolytic
graphite (HOPG) under high-fluence (10^(18)–10^(19) ions/cm^2) 30 keV Ar^+ ion irradiation at ion incidence
angles from θ = 0° (normal incidence) to 80° have been measured to trace both the structure and morphology
changes in the basal oriented samples. The target temperature has been varied during continuous
irradiation from T = -180 to 400°C. The surface analysis has been performed by the RHEED and SEM
techniques. The surface microgeometry was studied using laser goniophotometry (LGF). The dependences
of Υ(T) were found to be strongly non-monotonic and essentially different from the ones for Ar^+ and
N_2
^+ ion irradiation of the polygranular graphites. A sharp peak at irradiation temperature T_p 150°C
was found. A strong influence of electron transport anisotropy has been observed, and ion-induced
microgeometry is discussed
