New metal etching method for reducing electron shading damage

Abstract

Good quality Al/SiN x :H/InP metal-insulator-semiconductor devices obtained with electron cyclotron resonance plasma method Dry etch damage in GaAs metal-semiconductor field-effect transistors exposed to inductively coupled plasma and electron cyclotron resonance Ar plasmas J. Vac. Sci. Technol. B 15, 983 (1997); 10.1116/1.589518Effect of plasma polymerization film on reducing damage of reactive ion etched silicon substrates with CHF3+O2 plasmas J.This study proposes a new metal etching method for reducing electron shading damage using an inductively coupled plasma ͑ICP͒ etcher. Electron shading damage is caused by the same mechanism as in ''notch'' formation. Namely, negative charge-up of the sidewall of the photoresist by electrons due to the difference between electron and ion motion in the plasmas. We can therefore assume that an etching process with no notch will have low electron shading damage. The notch-free overetching process using low inductive power in an ICP etcher was found to have low and uniform electron shading damage. We also present an evaluation method for electron shading damage using a metal-nitride-oxide-silicon capacitor with a comblike antenna.

Effects of BCl3gas on physical damage and Al residues in oxide hard-mask-based Al etching

“…The results reveal that the formation of notching at the bottom corners of Al appears to be related to the heavy boroncontaining ions, e.g., BCl 2 + or BCl 3 + in the plasma during the OE step. A possible mechanism underlying the attacking of the Al corner by heavy ions is the electron shading model [10].…”

Study of the influence of gas chemistry on notching in metal etching

“…We also found that charging damage from electron shading effect occurred at the metal-oxidesemiconductor ͑MOS͒ transistors with a comblike (line/spaceϭ1/1 m) antenna. 11 In this article, we will describe the effect of overetching gas chemistry on notching and charging in metal etching using high-density plasma. A Cl 2 /BCl 3 plasma is widely used in metal etching.…”