1 January 2007 Evaluation of damage induced by electron-beam irradiation to metal-oxide semicondoctor gate pattern and method for damage-free inspection
Miyako Matsui, Syuntaro Machida, Toshiyuki Mine, Kazuyuki Hozawa, Kikuo Watanabe, Yasushi Goto, Jiro Inoue, Hiroshi Nagaishi
Author Affiliations +
Abstract
We analyze the electron-irradiation damage induced in wafers by scanning electron microscope (SEM) inspection, which uses SEM images of voltage contrast formed by the charges on the pattern. The effects of electron-beam energy and charging on a metal-oxide semiconductor (MOS) capacitor are studied. We find that the higher energy electron beam, whose electron range is larger than the thickness of the gate electrode, creates traps at the interface between the silicon substrate and the gate dielectric. The flat-band voltage is shifted by the created traps. Although these traps are created by the transmission of the electron beam into the dielectric, they are not created only by charging on the gate electrode; neither is an oxide fixed charge created in the MOS capacitor. Accordingly, for damage-free inspection of MOS devices, the electron-beam energy should be low enough that the electron range is smaller than the thickness of the gate electrode. On the other hand, the flat-band voltage does not shift, owing to charging on the pattern surface during the electron irradiation. However, the gate dielectric is broken down by charging on the gate electrode at high voltage. Accordingly, for damage-free inspection, the charging voltage should be controlled so as not to break down the gate dielectric.
©(2007) Society of Photo-Optical Instrumentation Engineers (SPIE)
Miyako Matsui, Syuntaro Machida, Toshiyuki Mine, Kazuyuki Hozawa, Kikuo Watanabe, Yasushi Goto, Jiro Inoue, and Hiroshi Nagaishi "Evaluation of damage induced by electron-beam irradiation to metal-oxide semicondoctor gate pattern and method for damage-free inspection," Journal of Micro/Nanolithography, MEMS, and MOEMS 6(1), 013009 (1 January 2007). https://doi.org/10.1117/1.2437195
Published: 1 January 2007
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Inspection

Dielectrics

Electron beams

Electrodes

Capacitors

Annealing

Molybdenum

Back to Top