GB/T 34210-2017Test method for determining the orientation of sapphire single crystal (English PDF)

1 Scope

This standard specifies the use of X-ray orienting apparatus to determine the sapphire crystal orientation.

This standard applies to the determination of sapphire crystal orientation parallel to the low index crystal plane.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version applies to this article

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 1555 semiconductor crystal orientation measurement method

GB/T 14264 semiconductor materials terminology

JB/T 5482 X-ray crystal orientation instrument

3 Terms and definitions

GB/T 1555, GB/T 14264 and JB/T 5482 defined terms and definitions apply to this document.

4 method principle

The crystal orientation is determined based on the X-ray diffraction principle. Single crystal is composed of three-dimensional periodic structure of atoms, can be seen as

Is a series of parallel planes formed by a vertical distance d of the atomic arrangement space when a bundle of parallel monochromatic X-rays is incident upon the plane and

Diffraction (reflection) occurs when the X-ray is irradiated with an optical path difference between adjacent crystal planes that is an integer multiple of its wavelength, that is, n times. Use counters to explore

Measured diffraction line, according to its location to determine the crystal orientation of single crystal, shown in Figure 1.

Figure 1 X-ray irradiation onto a single crystal plane geometric reflection conditions

When the angle theta between the incident beam and the reflecting crystal plane, the X-ray wavelength lambda, the interplanar distance d and the diffraction order n satisfy the following Bragg

The law (1), X-ray diffraction beam intensity will reach the maximum.

nlambda = 2dsintheta (1)

For the hexagonal system, the spacing d according to equation (2).