Single and molecular ion irradiation-induced effects in GaN: experiment and cumulative MD simulations

Abstract

An investigation of mechanisms of enhancement of irradiation-induced damage formation in GaN under molecular in comparison to monatomic ion bombardment is presented. Ionimplantation-induced effects in wurtzite GaN bombarded with 0.6 keV/amu F, P, PF2, and PF4 ions at room temperature are studied experimentally and by cumulative MD simulation in the correct irradiation conditions. In the low dose regime, damage formation is correlated with a reduction in photoluminescence decay time, whereas in the high dose regime, it is associated with the thickness of the amorphous layer formed at the sample surface. In all the cases studied, a switch to molecular ion irradiation from bombardment by its monatomic constituents enhances the damage accumulation rate. Implantation of heavy Ag ion, having approximately the same mass as the PF4 molecule, is less effective in surface damage formation, but leads to noticeably higher damage accumulation in the bulk.. The cumulative MD simulations do not reveal any significant difference in the total amount of both point defects and small defect clusters produced by light monatomic and molecular ions. On the other hand, increased production of large defect clusters by molecular PF4 ions is clearly seen in the vicinity of the surface. Ag ions produce almost the same number of small, but more large defect clusters compare to the others. This findings show that the enhancement of stable damage formation in GaN under molecular, as well as under heavy monatomic ion irradiation, can be related to the higher formation probabilityof large defect clusters.

Comparative study of radiation tolerance of GaN and Ga2O3 polymorphs

“…A large number of works have already been devoted to the studies of defect accumulation during the implantation of accelerated heavy and medium-mass ions into GaN [11][12][13][14][15][16][17][18]. In its turn, the data on ion-irradiation-induced defect formation in gallium oxide are limited and all the main results concern only the most stable β-phase [19][20][21][22][23].…”

Нелинейные Эффекты При Распылении Арсенида Галлия И Кремния Кластерными Ионами Висмута

“…Применение кластерных ионов в ионнолучевой литографии и наноструктурировании позволяет увеличить коэффициент распыления. Большое число работ (см., например, [2][3][4][5][6][7][8]) посвящено компьютерному моделированию процессов распыления и расчетам коэффициентов распыления. Вместе с тем публикаций об экспериментальных измерениях коэффициентов распыления кластерными ионами, а тем более данных о сравнительной эффективности распыления атомными и кластерными ионами в одинаковых экспериментальных условиях значительно меньше [9,10].…”