Using virtual parts to optimize the metrology process

Gaussian Process Regression for Virtual Metrology of Plasma Etch

Plasma etch is a complex semiconductor manufacturing process in which material is removed from the surface of a silicon wafer using a gas in plasma form. As the process etch rate cannot be measured easily during or after processing, virtual metrology is employed to predict the etch rate instantly using ancillary process variables. Virtual metrology is the prediction of metrology variables using...

Virtual Metrology Software Tools and Techniques for Feature Extraction of Spiral Bevel Gear Errors

The main objectives of multi-axis machining are to achieve perfect surface quality, precision, and speed without any need for re-machining. Within cutting processes, a strong integration of technologies such as virtual machining and inspection algorithms is important [1]. Closed Loop Machining (CLM) is an important method to maximise the efficiency of cutting processes, and automatic data colle...

Three-dimensional metrology with the virtual fitting gauges

The metrology implemented in several classical software equipping the coordinate measuring machines, does not correspond to the standardized tolerancing by zones, virtual conditions and perfect datum features fitted outside the matter. On the basis of these concepts and by generalizing them, a conceptual model of "fitting virtual gauges" is presented. On a part presenting two positional toleran...

Gaussian Process Regression for Virtual Metrology of Microchip Quality and the Resulting Strategic Sampling Scheme APPROVED BY SUPERVISING COMMITTEE: Dragan Djurdjanovic, Supervisor Roman Garnett Gaussian Process Regression for Virtual Metrology of Microchip Quality and the Resulting Strategic Sampling Scheme

Numerical and analytical investigation of an ultrasonic assisted ECAP process

One of the great challenges in the processing of materials using Equal Channel Angular Pressing (ECAP) is the high forming forces required to produce large shear deformation in the material. Researchers show that the friction forces between the die and the sample constitute a great part of the total forming forces. Recently, ultrasonic vibrations are successfully implemented into the ECAP proce...