High speed, dry etching of Fe for integration of magnetic devices in microelectronics

Abstract

Articles you may be interested inA high-speed magnetic tweezer beyond 10,000 frames per second Rev. Sci. Instrum. 84, 044301 (2013); 10.1063/1.4802678 High-force NdFeB-based magnetic tweezers device optimized for microrheology experiments Rev. Sci. Instrum. 83, 053905 (2012);Dry etch behavior of Fe in inductively coupled chlorine-based plasma at elevated temperatures has been investigated. Etch rates up to 300 nm/min at 190°C were achieved, with good selectivity towards SiO 2 and Al 2 O 3 masks. Etching did not take place in pure Cl 2 plasma or Ar/Cl 2 plasma, but required the addition of a few percent BCl 3 or SiCl 4 . The process was found to be a combination of spontaneous and ion enhanced chemical etching. Simultaneous exposure to ultraviolet light from an external source did not enhance the etch rate, but did shorten the inhibition time of the etching.

Etching of iron and iron–chromium alloys using ICP-RIE chlorine plasma

“…They observed a maximum etch rate at 50% Cl 2 , and a strong increase in etch rate between 0 and 25% Cl 2 . These results, in association with Andriesse's findings [36], show that Fe can be sensitive to chemical etching with neutral Cl, with a dependence on the substrate temperature. FeCl 3 has a vaporization temperature of 316 • C at atmospheric pressure [38].…”

“…They measured an etch rate of 100-150 nm/min for N i and F e in some conditions. Andriesse et al [37] observed a strong increase of F e etch rate when the substrate temperature increases from 70 to 200 o C, while the etch rate slowly increases with bias from 0 to -75 V . XPS (X-Ray Photoelectron Spectroscopy) analyses revealed the presence of F e − Cl bonds, proving the chemical adsorption of Cl on the surface etched by Cl 2 /BCl 3 .…”