Solid phase epitaxial regrowth of ion beam-amorphized α-quartz

Abstract

Solid phase epitaxial growth of ion beam-amorphized α-quartz has been studied by means of Rutherford backscattering spectrometry in channeling geometry. α-quartz single crystals were irradiated with Cs+ and Xe+ ions and annealed in air or in vacuum at 500–900 °C. Complete epitaxial regrowth has been observed in the Cs-irradiated samples, after 875 °C annealing in air. On the other hand, vacuum annealing provided only incomplete regrowth of the amorphous layer, while Xe-irradiated α-quartz could not be regrown up to 900 °C. The behavior of Cs in the recrystallization process is discussed in terms of the SiO2-network topology.

Na-irradiated alpha-quartz: chemical epitaxy and luminescence

“…The basic mechanism of epitaxial regrowth of ionirradiated quartz has been discussed by Roccaforte et al [6][7][8] using ideas developed by Spaepen, Turnbull, and others [14][15][16][17]. It is noteworthy that, in all the cases with implanted alkali ions studied so far, the epitaxy of the amorphized layer, the out-diffusion of the alkali ions, and the oxygen exchange between the SiO 2 matrix and the annealing gas are highly correlated [4,6].…”

“…It is noteworthy that, in all the cases with implanted alkali ions studied so far, the epitaxy of the amorphized layer, the out-diffusion of the alkali ions, and the oxygen exchange between the SiO 2 matrix and the annealing gas are highly correlated [4,6]. The most important reaction step consists in binding an implanted alkali ion A to the dangling oxygen ion, which is produced as radiation damage during the implantation of A (or any other ions) [4,6]. In the presence of migrating oxygen (O * ), this process can be described as…”

“…Since doping quartz by ion beam implantation disturbs or even destroys its crystalline long-range order, many attempts at solid-phase epitaxial regrowth of the damaged/amorphized layers by means of dynamic, chemical, or laser-annealing epitaxy have been made [4][5][6][7][8]. Alkali-ion implantation of α-quartz followed by thermal annealing in air or oxygen, a process called chemical epitaxy, indeed provides complete epitaxy around 1100 K [4,[6][7][8][9][10][11]. The recrystallization is accompanied by alkali out-diffusion and oxygen exchange between the annealing gas and the matrix, as verified by Rutherford backscattering channeling spectroscopy (RBS-C) and time-of-flight elastic recoil detection analysis (TOF-ERDA) after annealing the samples in 18 O 2 tracer gas [4, 6-8, 10, 11].…”

Solid phase epitaxy of Na-ion irradiated α-quartz: Cathodoluminescence, kinetics and surface morphology

“…For the various ions, epitaxy starts only above critical temperatures and ion fluences. These results were obtained by ion-beam analyses, such as Rutherford backscattering (channeling) spectrometry (RBS, RBS-C) and elastic recoil detection analysis (ERDA) [3][4][5][6], and were explained with the help of the concept of the SiO 2 network topology [7,8].…”

“…In recent years, we have investigated the processes and mechanisms of solid phase epitaxial regrowth (SPEG) in alkali-ion implanted a-quartz during thermal annealing in oxygen and air [3][4][5][6]. The dependence of SPEG on appropriately selected ion species (Li, Na, Rb, Cs), their fluences and annealing conditions (such as type of annealing gas, annealing time and temperature) have been studied.…”