From Idea to final MEMS Layout – Automating the Design Process

Getting from an idea of what a next-generation accelerometer or gyroscope might look like to a manufacturable layout involves many complex simulation steps. Normally, many redesigns and a variety of software tools are used to arrive at a feasible layout that meets the target specifications and can be fabricated within manufacturing tolerances. One of the main problems is that switching between software tools or setting up a new simulation run requires a lot of manual input, which can lead to errors in implementation or making too many assumptions, leading to unexpected results and redesigns.

The i-ROM Modelbuilder envisions a development chain, where the entire simulation flow is seamlessly automated as much as possible.

First, we start in the i-ROM Sketcher, where the mask layout can be sketched in traditional 2D fashion. For the design process, we have parameterizable library elements from comb cells to springs to mass bodies. In addition, we can import existing GDS files. The created layout is then loaded into the i-ROM Modelbuilder core where it extrudes the 2D design into 3D and automatically applies the process data (PDK) to each shape such as mask undercut, corner rounding and etch side wall slopes. In the Modelbuilder, we can then run all types of simulations (modal, static, transient and harmonic) with unprecedented speed because we have perfected the Reduced-Order-Modeling ROM method in our own i-ROM FEM core.

If the simulation results are satisfactory, we offer a variety of interfaces to other software solutions because our customers have their own specialized tool to further improve the design and implement their own intellectual property. This includes model export of sensor behavior to Matlab Simulink and Verilog, 3D geometry export with all PDK settings and mesh to other FEM software such as Ansys or Comsol, and other customer specific interfaces. Often the last step is the layout export to GDS where the complete sensor including bond pads, wiring and fillers is generated. This layout is merged with the manufacturer specific layout (like protective layers, bondframe, etc.) and sent directly to the manufacturer.