The characteristics of high etch rate ion beam etcher with magnetized inductively coupled plasma source

摘要

In this paper, newly designed magnetized inductively coupled plasma ion beam etcher (M-ICP IBE) is proposed. Plasma density and electron temperature were measured with respect to the magnetic flux density and to the source power. In addition, ion energy distribution and ion flux, the result of which were correlated with plasma density and electron temperature characteristics, were measured. The relationship among plasma density, electron temperature, and the diameter of a screen grid hole were also studied in order to extract optimized ion beam from the grid layer. Besides, the ion beam characteristics with respect to the screen grid voltage and to the acceleration grid voltage were investigated. Meanwhile, the dry etching characteristics of SiO_2 in ICP IBE and that of M-ICP IBE were investigated. It was confirmed that the beam extracted from the grid layer in M-ICP IBE showed high ion flux even at low ion energy, where ICP IBE showed much lower ion flux. As a result, the etch rate of SiO_2 in M-ICP IBE was about seven times higher than that in ICP IBE.