A Note on Response Time Minimization for Planar MSM Photodetectors

The finger sizing of interdigitated Schottky-barrier metal-semiconductor-metal photodetectors (MSM-PD) is discussed in this paper. We observe that a wide variety of design objectives and constraints have a special form, i.e., they are (either approximately or exactly) posynomial functions of the design variables. Therefore an MSM-PD geometry with fast response speed can be determined by solving a special form of optimization problem called posynomial programming, for which very efficient global optimization methods have been developed. Our method, therefore, yields automated finger sizing of MSM-PD, directly from specifications.