`Non-critical' levels such as implant layer consume a large volume of photoresist. This work was done to choose a cost- effective, high performance implant resist implant resist. IN addition to resolution considerations, outgassing during implant, speed and cost were all evaluated to choose the successful candidate. Through this effort a new resist formulation, SumiresistTM PFM-10 was compared with other existing I-line formulations.
This paper reports on a single coat process optimization of a new positive thick film resist originally described by Renaldo et al. from IBM at SPIE in 1995. The positive diazonapthoquinone photoresist system, SJR-3000, can achieve uniform coatings of greater than 28 microns in a single coat. In addition the process can produce images with wall profiles greater than 80 degrees and is compatible with traditional etch baths as well as gold, copper and permalloy plating baths without exhibiting cracking. Process latitude over a wide range exposure and development conditions will be demonstrated at a 20 (mu) coating thickness using a stepper exposure system.
The aggressive drive to reduce device geometries to submicron levels while utilizing ULSI design rules has posed many challenges to traditional semiconductor process technologies. For example, as photolithographic hardware manufacturers, and engineers, begin to define and develop the next generation systems, it has become apparent that process margins are severely minimized with respect to the capability of existing hardware. As a result, all aspects of the process, especially the chemistry of the resist and develop modules, must be optimized and thoroughly understood to provide maximum process latitude. The work described in this publication details a process optimization effort that led to a manufacturable, single layer, G- line lithographic system capable of achieving and maintaining the necessary process control designated by aggressive design specifications. The photolithographic process was characterized using Advanced Engineering Techniques, as defined by Genichi Taguchi, in conjunction with Response Surface Methodology (RSM) multilevel statistical experimental designs. Optimized conditions resulted in a process capability of greater than 1.5 Cpk control when measured in reference to critical dimension performance. As a result, the newly defined system is capable of operating far beyond the scope of the more traditional systems, and has allowed for the manufacture of products necessary to compete in the advanced IC marketplace.