<title>Plasma etching of high-temperature-deposited AlSiCu for submicron ULSI manufacturing</title>

Abstract

To achieve good step coverage for submicron contacts/vias, many approaches have been taken in recent years in VLSI production. While CVD tungsten plug is widely implemented in US for submicron manufacturing, planarized aluminum plug (i.e. high temperature aluminum deposition) is slowly emerging for its process simplicity and low wafer cost. In this paper, we will present the plasma etching studies on the high-temperature-deposited AISiCu (or hot aluminum) and its application in manufacturing of ULSICs' with O.6j.tm design rules. The etchability and manufacturability of this high temperature-deposited A1SiCu have been proven and demonstrated with submicron metal lines. Various aspects of the hot aluminum etching including profile control, residue, microloading and resist selectivity are discussed in detail.

Effects of process parameters on microloading in subhalf-micron aluminum etching

“…Although profile microoading effect should be under control, the etch rate microloading effect could be quite serious if the etching process condition is not optimized [1]. Etch rate microloading effect causes the decrease of etch rate with decreasing pattern size and open area [2,3].…”