Sergio Edelstein

Ionized metal plasma deposition of titanium and titanium nitride for deep contact applications

The characteristics of ionized metal plasma PVD Ti-TiN films have been investigated for the application as a liner for small deep contacts. Compared to collimated Ti-TiN films, the bottom coverage of IMP Ti-TiN is more than two times higher at high aspect ratio contacts. With substrate bias, IMP Ti and IMP TiN show different crystallographic orientation behaviour. When applied to deep contacts, excellent contact resistance was achieved with thinner IMP Ti films, which is only one third of the thickness of collimated Ti films. Adopting the IMP TiN liner also represents a lower contact resistance than collimated TiN liners.

Using cost of ownership (COO) modeling to optimize productivity and wafer output of sputtering tools

The SEMATECH COO model has been used as a design tool to optimize the hardware and application-dependent configurations of the Endura PVD system. The model helped identify and quantify the effects of improved equipment hardware, configurations, and processes. Sensitivity analyses were performed to determine the effect of throughput, chamber and system maintenance down time, reliability, equipment cost, consumables life and cost, and system configuration on cost per wafer (CPW) and wafer starts per week (WSPW). The results indicate that throughput and preventive maintenance down time have the greatest impact on COO. Equipment components were selected or designed and processes and procedures were developed to minimize the CPW and maximize the WSPW per tool. Increases in WSPW of 40 to 60% have been achieved by increasing overall throughput, decreasing PM time, and optimizing PM scheduling. These improvements can yield up to 25% reduction in cost per wafer.