Dust Plasma Effect on the Etching Process of Si[100] by Ultra Low Frequency RF Plasma

Ahmed Rida Galaly, Farouk Fahmi Elakshar

Engineering Science Department, Faculty of Community, Umm Al-Qura University, Mecca, Saudi Arabia.
Physics Department, Faculty of Science, Al-Azhar University, Cairo, Egypt.

DOI: 10.4236/jmp.2013.42030                

Abstract

Dust-plasma interactions play vital roles in numerous observed phenomena in the space environment, their scope in the industrial laboratory has grown rapidly in recent times to include such diverse areas as materials processing, microelectronics, lighting and nuclear fusion. The etching processes of Si wafer has been studied using Ultra low frequency RF plasma (ULFP) at (1 KHz) by two different techniques namely: ion etching using inert gas only (e.g., argon gas), and ion chemical etching using an active gas (beside the inert gas) such as oxygen. In the case of large dust particle, the dust might act as a floating body in the plasma collecting equal fluxes of electrons and ions. The velocity of the ions flux out from the mesh (cathode) and cause ion sputtering for the sample (Si-Wafer) measured, moreover the rate coefficient for collection of electrons and ions by dust (K) is calculated here, the presence of dust, however, may itself cause loss process. As the plasma density increases, the etching rate increases and the volumetric rate of loss of electron and ions due to dust particle increases (K). A comparison between the volumetric rate of loss (K) due to ion chemical etching (75% Ar/25% O₂) and ion etching (Pure Ar) has been carried out.

Keywords

Dust Plasma; Ultra Low Frequency; Ion Etching; Ion Chemical Etching; Volumetric Rate of Loss

Conflicts of Interest

The authors declare no conflicts of interest.

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