Creation of silicon submicron structures by compression plasma flow action

Abstract

Oriented submicron cylindrical structures obtained in a single pulse treatment of silicon monocrystal by compression plasma flow are described. The nitrogen plasma flow generated by magnetoplasma compressor is used for modification of Si (1 1 1) monocrystal surface. The speed of plasma flow was up to 40 km/s depending on input energy and gas used and its pressure. The electron density and temperature within the region of plasma flow maximal compression was up to 2 × 10 17 cm -3 and 20,000 K, respectively. Silicon samples placed perpendicular to the flow were exposed to a single 100 μs plasma pulse driven by the discharge current of 70 kA. Typical dimensions of cylindrical structures formed at the crystal surface are 0.1-2 μm in diameter and up to 200 μm in length. The influence of external magnetic field on the dimensions of the cylindrical structures was also investigated. The large diameter cylindrical structures have been noticed to exhibit the hollow features. The catalyst was not used in the process of silicon surface modification. © 2004 Elsevier Ltd. All rights reserved.