An X‐Ray Technique for Evaluating the Structure of Films for Device Applications

Thin films are composed of many crystallites. Where such films are used in the construction of devices it is frequently necessary to grow them with a preferred orientation. A quick, non destructive method to measure the degree of orientation could provide a useful guide to device performance. We have investigated a technique to obtain this information using the Philips P.W. 1050/25 diffractometer. The method depends on being able to tilt the film out of the diffracting plane of the diffractometer and can be used for films in which all crystallites are orientated to better than ±25°, of the preferred direction. This limit is generally acceptable since greater misorientation will normally produce a poor device. The axial beam divergence of the diffractometer is shown to limit the accuracy of the technique for very highly orientated films. Experimental Verification of the method is described.