SU855457A1 - Device for investigating monocrystal structural perfection - Google Patents

Description

one

This invention relates to the study of the structural perfection of mono-; crystals with the help of secondary processes r accompanying them by x-ray irradiation under conditions of Bragg diffraction.

A device for studying the structural perfection of single crystals is known, which contains an x-ray source, a single crystal holder, an optical detector that detects the luminescence of a single crystal under study 1

However, in this device, luminescence is excited in the absence of x-ray diffraction on the single crystal studied, which leads to a low sensitivity to structural defects of the crystal under study.

The closest technical solution is a device for studying the structural perfection of single crystals, which contains an x-ray source, a crystal monochromator, a collimator, a single crystal holder with a goniometric device, and a secondary emission detector of the single crystal under investigation. In this device, fluorescent radiation from photoelectrons and Auger electrons 2 are used as the secondary emission of the monocrystal under investigation.

However, despite the wide functionality of this device, it lacks the ability to study the interrelation of structural defects of the single crystal under study and X-ray processes.

The purpose of the invention is to provide

opportunities to obtain additional

15 information on structural defects of the single crystal under study.

The goal is achieved by the fact that in a device for the study of structural coBeiMieHCTBa MO20 J crystals, containing an X-ray source, installed along the X-ray beam, a crystal-monochromator, collimator, holder of a single crystal

2 with a goniometric device (X-ray detector), a secondary emission detector of a single crystal under investigation, located opposite the holder, as a secondary detector

an optical radiation detector of the luminescent sample was used, two interrupters were inserted into the device, one of which was installed in the path of the primary X-ray beam and the second in front of the optical detector, and control devices for interrupters so that at any given time in the radiation transmission position there is only one pre-. jerk.

In this case, the breakers are made in the form of discs with holes, and the control means are made in the form of a device for synchronous rotation of the breakers.

The drawing shows a variant of the device with the removal of the luminescent radiation of the investigated single crystal on the reverse side of the incident x-ray beam.

A device for studying the structural perfection of single crystals contains an X-ray source 1, a monochromator crystal 2, a collimator 3, a single crystal 4, mounted in a holder with a goniometric device (not shown), an X-ray detector 5, an optical detector 6, interrupters 7 and 8, the first of which is installed in the path of the x-ray beam 4 incident on the monocrystal 4, and the second is installed in the path of the luminescent radiation of the monocrystal under investigation going to the optical part Vector 6. Breakers 7 and 8 are made in the form of disks synchronously rotating from drive 9, and are provided with openings (or hole systems) 10 and 11.

The device works as follows.

A monochromatic collimated x-ray beam is incident on the monocrystal 4 under study at the Bragg angle, which is established in a known manner with the help of a goniometric holder device and an X-ray detector 5. In this case, the beam passes through the opening 10 of the chopper 7. The luminescent radiation generated in the monocrystal is not delayed by the interrupter 8 and does not reach the detector 6. When the interrupters 7 and B are brought into joint rotation after a certain time interval, the opening 11 in the interrupter 8 provides the luminescent afterglow of the investigated monocrystal 4 to the optical detector 6, which can be made in any known manner, in particular, be a photographic camera. By setting the speed of rotation of the interrupters, it is possible to adjust the afterglow time of the single crystal under study. When using hole systems in each chopper so that one hole 10 in chopper 7 has several holes 11 in chopper 8, it is possible at one speed of rotation to register afterglow of different duration, which refers to defects of different types. The detector 6 can be spectrally sensitive, which also allows the amount of information obtained about the defects of the structure of the single crystal 4 to be expanded.

The advantages of the device are its constructive simplicity, since the registration of luminescence does not require a vacuum chamber, which is necessary in the study of secondary electron emission.

In addition, this device can be equipped with means of measuring secondary processes of another type (fluorescence, photoelectric emission), similarly to the known device.

Claims (2)

Apparatus of the Invention For the study of the structural perfection of single crystals containing an X-ray source, a monochromator crystal mounted on an X-ray beam, a collimator, a single crystal with a goniometric device (X-ray detector), a single-crystal detector located in front of the sample to be examined, and a X-ray detector located opposite the holder. Applied to the fact that, in order to provide the possibility of obtaining additional information on the structural x defects of the monocrystal under study, an optical detector of the luminescent glow of the sample was used as a secondary emission detector, two interrupters were introduced into the device, one of which was installed in the path of the primary X-ray beam and the second in front of the optical detector, and the control means of the interrupters were thus at any given time, only one chopper is in the radiation transmission position. 2. The device according to claim 1, wherein the switches are made in the form of discs with holes, and the control means are made in the form of a device for the synchronous rotation of the breakers. Sources of information taken into account in the examination 1. Luminescent analysis of GIFML, M., 1961, p. 156. 2. Authors certificate of the USSR 543858, cl. G 01 N 23/22, 1975 5 prototype).