Method of layer thickness measurement

Measuring and testing – Vibration – By mechanical waves

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

G01N 2900

Patent

active

046255567

ABSTRACT:
The layer thickness of an object including a substrate and a layer formed thereon is measured by the following steps. First, with regard to a reference system consisting of a reference substrate and a reference layer formed thereon, which are formed of the same materials as those of the object, and an ultrasonic wave propagation medium, the incident angle .theta. at which an ultrasonic wave is applied through the propagation medium to the reference layer and the product H of the frequency of the ultrasonic wave and the thickness of the reference layer are calculated, the incident angle .theta. and product H having such values as minimize the intensity of the ultrasonic wave reflected from the reference layer. The layer of the object is put in contact with the ultrasonic wave propagation medium, and an ultrasonic wave is applied to the layer through the propagation medium at the incident angle .theta.. Then, the frequency of the ultrasonic wave reflected from the layer is measured to detect the frequency of the incident ultrasonic wave for the minimum reflected wave intensity. The thickness of the layer of the object is calculated from the detected frequency and the value H.

REFERENCES:
patent: 4098129 (1978-07-01), Deblaere et al.
patent: 4274288 (1981-06-01), Tittmann et al.
J. L. Rose et al., Materials Evaluation, Dec. 1974, pp. 249-258.
Wilson et al., Journal of Applied Physics, 55(9), 1 May 1984, pp. 3261-3275.
Yamanaka, Journal of Applied Physics, 54(8), Aug. 1983, pp. 4323-4329.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method of layer thickness measurement does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of layer thickness measurement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of layer thickness measurement will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2286401

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.