Process transfer from conventional RIE to transformer-coupled high density plasma metal etch system

One of the most challenging processes in semiconductor manufacturing is the dry etching of aluminum alloys in plasma. The requirements include: anisotropy, high selectivity to photoresist, control of critical dimensions, residue free etching, and minimal pattern sensitivity. Along with these requirements, a post etch treatment is needed to prevent the onset of corrosion. In a manufacturing environment, high throughput, minimal down time, and low cost of ownership are essential. IBMs Advanced Semiconductor Technology Center (ASTC) was a beta site for the LAM 9600 metal etch tool. Plasma enhancement, in this system, is achieved using TCP (transformer coupled plasma). With TCP, a high density plasma is generated in a wide pressure range (5 to 100 mTorr) allowing for improved process capabilities. Post etch treatment, on the 9600 system, consists of two parts: a photoresist stripper module and a atmospheric passivation module. This paper will discuss the LAM/IBM ASTC beta site tool install, debug, and process transfer/qualification experience. Electrical data, critical dimensions, particle performance, etch rates, uniformities, selectivities, etch profiles, and tool availability will be compared to the LAM 4608 system