Share Email Print

Journal of Micro/Nanolithography, MEMS, and MOEMS

Quantitative measurement of voltage contrast in scanning electron microscope images for in-line resistance inspection of wafers
Author(s): Miyako Matsui; Takayuki Odaka; Hiroshi Nagaishi; Koichi Sakurai
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

We develope an in-line inspection method for partial-electrical measurement of defect resistance, which is quantitatively estimated from the voltage contrast formed in a scanning electron microscopy (SEM) image of an incomplete-contact defect. We first manufacture standard calibration wafers for the voltage-contrast calibration. The contact resistance of systematically formed defects varied from 108 to 1017 . Then, we quantitatively analyze the gray scales of these defect images captured using a review SEM. As a result, calibration curves for estimating the contact resistance of the incomplete-contact defect are obtained at a probe current of 60 pA and a charging voltage of 4 V. The estimated contact resistance is between 107 and 1012 . Finally, this inspection method is applied to wafers manufactured for a static random access memory device. Accordingly, the gray scales of defective plugs formed for shared contact patterns are classified into two levels. The resistances of these defects are estimated from the calibration curve. The estimated resistances of the lower contrast defects (with an accuracy of about one order of magnitude) agree well with the resistances measured using a nanoprober. The resistances of the higher contrast defects are estimated as well, although they are too high to be measured using a nanoprober.

Paper Details

Date Published: 1 October 2010
PDF: 6 pages
J. Micro/Nanolith. 9(4) 041304 doi: 10.1117/1.3514702
Published in: Journal of Micro/Nanolithography, MEMS, and MOEMS Volume 9, Issue 4
Show Author Affiliations
Miyako Matsui, Hitachi, Ltd. (Japan)
Takayuki Odaka, Hitachi, Ltd. (Japan)
Hiroshi Nagaishi, Renesas Technology Corp. (Japan)
Koichi Sakurai, Renesas Technology Corp. (Japan)

© SPIE. Terms of Use
Back to Top