Study on the influence of doping process on resistance of semiconductor bridge region

Semiconductor bridge (SCB) is the most important component in MEMS electrothermal transducer. Since the energy conversion is relalized through Joule-Lenz law, the resistance of SCB plays a very important role in MEMS electrothermal transducer. The doping process has direct influence on the resistance of SCB and requires careful design. Based on target sheet resistance and junction depth of SCB, process parameters of ion implantation and annealing is determined by theoretical analysis. The TCAD for simulation using these parameters results in a difference from the target value of only 6% in sheet resistance and only 13% in junction depth. We also established a model for SCB resistance model, which is a function of the silicon resistivity. SCB samples is also fabricated using these process parameters and the resistivity calculated by the measured resistance is only 8% different from the target value. This work has provided guidance for the SCB design and for determining the process parameters regarding ion implantation and annealing.