Modification of inductively coupled plasma characteristics by introducing a metal grid

Abstract With the advancement of semiconductor manufacturing processes, etching technology has to satisfy more stringent requirements, such as reduced ion bombardment damage, enhanced plasma uniformity, tunable electron energy probability distribution function (EEPF), and so on. The implementation of a metal grid in inductively coupled plasmas (ICPs) offers a promising approach to address these challenges. This study employs a 2D fluid/electron Monte Carlo collision hybrid model to investigate the effects of grid height and number of metal blocks on the electron density, electron temperature, plasma potential, EEPF and ion energy distribution function (IEDF). The results demonstrate that by comparing with conventional ICP configurations, introduction of a metal grid could obviously increase the electron density above the grid, while the magnitude below it is reduced remarkably. Additionally, both the electron temperature and ion energy beneath the grid are notably lower than in grid-free setups. The number of metal blocks has a pronounced impact on the IEDF, with the ion energy peak shifting from 9.5 eV to 7 eV. In contrast, the axial position of the metal grid has minimal effect on the IEDF. Precise tuning of grid height and block number enables refined control over both the plasma properties and particle dynamics.