Novel submicron process development tool for SAW device fabrication

SAW device performance is highly dependent on linewidth and metal edge quality. Small changes in each can have strong effects on device performance. At submicron linewidths, detecting these changes is often challenging. The limited field of view at higher magnifications can make accurate navigation between and within similar test structures difficult. Our objective in this work is to determine the process parameters needed to fabricate SAW resonator devices having a/p values of 0.6 for periods of 0.5μm and 0.6μm using contact lithography and a liftoff process. A novel test pattern that will enable efficient and accurate navigation of submicron test structures during high magnification scanning electron microscopy (SEM) will be presented. Using these test structures we can evaluate the a/p and line edge quality for each linewidth/ period group. For the first test mask no linewidth compensation was made to account for processing variations. Based on measured results, a second mask was then designed to compensate for the observed bias, in order to obtain the desired a/p.