Credence Systems Corporation

Martin D Leibowitz

Romain Desplats

Kenneth R Wilsher

Philippe Perdu

Patricia Le Coupanec

Praveen Vedagarbha

Felix Beaudoin

Girish Dajee

Methods, apparatus and data structures useful in correcting PICA image data are described. An exemplary method comprises acquiring optical image data of a target having identifiable optical-image features, acquiring PICA image data of the target having identifiable PICA-image features corresponding to the optical-image features, matching PICA-image features with corresponding optical-image features, and calculating from matched PICA-image features and optical-image features a set of coefficients defining relationships between observed positions of PICA-image features and optical-image features. Corrections are applied to the observed positions of detected photons based on the coefficients. The coefficients may provide a local correction using a bilinear relationship giving the transformation of a rectangle formed by four features of the PICA-image data to fit a corresponding rectangle in the optical-image data. Alternatively, the coefficients may provide a global mapping function defining transformation of any point of the PICA-image data to fit a corresponding point in the optical-image data.

PICA system detector calibration

A method and apparatus for laser-assisted fault mapping which synchronizes the laser control with the tester unit. The inventive method provides for laser-assisted pseudo-static fault mapping to localize defects in a device whose inputs are being stimulated dynamically by a tester. It further provides for laser-assisted dynamic soft error mapping, to localize in terms of location and to correlate with respect to a specific test vector, sensitive areas in a device by utilizing device performance criteria such as pass-fail status outputs. The apparatus includes a fully controllable dynamic laser stimulation apparatus connected to a control unit that provides complete synchronization with a tester unit.

Spatial and temporal selective laser assisted fault localization

Growing community of inventors

Fremont, CA, United States of America

Martin D Leibowitz