AnisE is an easy-to-use anisotropic etch process simulation tool for MEMS design and process control

Demystifying etch behavior

Anisotropic etching is one of the most difficult silicon micro-machining processes to model, often considered in the realm of the “black arts.” It can be challenging to grasp intuitively due to the complex nature of evolving etch fronts. In fact, many companies have developed closely guarded etch secrets through trial-and-error experimentation.

Well, those days have ended. AnisE simplifies the process of accurately simulating etch behavior. Import your mask, choose your wafer orientation and your process parameters, and then watch the etch progress online before your eyes!

Cellular automata

Unlike other tools that utilize heuristic methods to calculate propagation of etch planes, AnisE is a cellular automata-based simulation. What does this mean? That other tools fail to provide accurate results for complex masks and long etch times. With AnisE, you can choose any mask configuration, however complex, throw in double-sided etching and add etch stops. It’s easy!

Sophisticated controls

AnisE comes with built-in etch databases for KOH and TMAH. It automatically updates the etch rates as a function of temperature and concentration. 

With AnisE, you can simulate single or double-sided <100> and <110> etching. You can incorporate multiple etch stops, steps or anything else you can do in the real world. In addition, you can study the effect of mask misalignment, the effect of combining RIE etching with anisotropic etching and many other real- world conditions.

Whether you are interested in studying process variation or designing corner compensation features, AnisE will become an invaluable part of your process toolset.

Comprehensive Capabilities

AnisE is capable of predicting the effects of etchant temperature, concentration, and etch time on the final 3D device geometry. Corner compensation and process tolerances can be modeled and visualized with AnisE. Creating correct geometries based on proper etch parameters before entering a fabrication facility saves resources otherwise spent on multiple prototype iterations.

By creating or importing a mask file, users can:

• • Simulate <100> or <110> wafer orientation etching
• • Simulate etching under different time, temperature, and concentration parameters
• • Access TMAH and KOH etch-rate databases, or use customized etch-rate data
• • Etch the top, bottom, or both sides of a wafer
• • Implement multiple protective etch stops
• • Perform multiple etchings with different masks on a single wafer
• • Study the effects of misalignments and other process deviations
• • Determine the effects of vertical etching coupled with anisotropic etching
• • Perform 3D geometric visualization and cross-sectioning
• • Take distance measurements on the etched wafer
• Visualize and export 3D results in DXF and VRML formats