Damage of silicon induced by low-energy Ar magnetron discharges

Abstract

The physical damage induced in silicon by argon magnetron discharges has been studied. The surface trap density measured with the high-low frequency capacitance-voltage method was used to evaluate the degree of damage on the substrate. No damage is found for substrates sputter-etched in an RF discharge with 3 0 eV mean ion energy. Substrates sputter etched in 450 eV DC discharge show damage similar to that obtained in other glow discharge or ion milling systems with the same energy.

New Features of Dark and Photoconductivity Response of Low Energy Ar+ Ion bombarded GaAs

“…It is desired that such substrates not be damaged during low energy ion processing steps. However, near-surface damage does occur, and has been extensively reported, both for GaAs [1][2][3][4][5][6] and other substrate materials [7][8][9]. Measurement techniques reported in these studies include I-V, C-V, DLTS, Auger, XPS, LEED, photoluminescence, Rutherford backscattering, photovoltaic response, thermally stimulated current, Raman spectroscopy, optical absorption, ellipsometry and Kelvin probe.…”

Anatolii Dmitrievich Myshkis (on his seventieth birthday)

“…The damage to a semiconductor substrate processed in the glow discharge has been extensively studied using contact destructive techniques [1][2][3][4]. It has been found that the damage level decreases with the ion energy of the glow discharge [2,3].…”

“…It has been found that the damage level decreases with the ion energy of the glow discharge [2,3]. Of particular interest is the fact that no damage to the Si substrate was observed in the case of the Ar magnetron discharge with 30 eV ion energy [4]. Since the energy threshold for Si atomic displacement is only -20 eV [ 5 ] , the Ar magnetron discharge with 30 eV ion energy should be able to induce damage.…”

“…Since the energy threshold for Si atomic displacement is only -20 eV [ 5 ] , the Ar magnetron discharge with 30 eV ion energy should be able to induce damage. Thus the vanishing of this damage in [4] was believed to be caused by thermal annealing in the sample preparation for the capacitance-voltage (C-V) measurement [4]. In this paper, this damage will be revealed by a contactless, non-destructive technique, namely photoinduced modulation absorption (PMA) [&S].…”

“…The substrates being processed were well chemically polished n-Si wafers of 51 mm diameter, 250pm thickness, 5-10 Q cm resistivity and (111) orientation. The process was carried out in the hollow oval magnetron discharge system, in exactly the same way as in the previous work [4]. The RF 200 W Ar magnetron discharge having 30 eV mean ion energy was used in the present test.…”