JPH0672933B2 - X-ray semiconductor detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial field of application" The present invention relates to an X-ray detector used in the detection of X-rays when the film thickness during film formation is measured by X-ray measurement in ultrahigh vacuum.
Line semiconductor detector.

"Prior Art" The main body used in this type of X-ray semiconductor detector has a PIN structure in which lithium is mainly diffused in silicon. Upon incidence, a number of hole-electron pairs that are proportional to the energy are created, and this is taken out as an electric pulse. This detector has high energy resolution, but on the other hand, unless the detector body is always cooled to the liquid nitrogen temperature (77 ° K), lithium diffuses and the performance deteriorates.

FIG. 2 shows a conventional X-ray semiconductor detector. Liquid nitrogen 12 is enclosed in a heat insulating bottle 11 for liquid nitrogen. As a heat transfer body for transferring the heat of the liquid nitrogen 12, one end of a heat transfer rod 13 is arranged in contact with the liquid nitrogen 12. A semiconductor detector body 14 is attached to the other end surface of the heat transfer rod 13 so as to be in contact therewith.
A housing 15 having a heat transfer rod 13 and a semiconductor detector 14 therein is provided. One end of the inside of the housing 15 communicates with the vacuum system of the heat insulating bottle 11 for liquid nitrogen. The other end of the casing 15 is connected to the detected X-ray source 17 by a flange 16, and the casing 15 and the detected X-ray source 17 are connected.
Is in communication with. The semiconductor detector body 14 is connected to an electric connector 19 provided on the housing 15 through a signal line and a power supply line 18. Detected X-ray source 17 of semiconductor detector body 14
On the side, a housing 15 is provided with a gate valve 21 capable of blocking both sides.

[Problems to be Solved by the Invention] As described above, in the conventional X-ray semiconductor detector, the vacuum system of the liquid nitrogen heat insulating bottle 11, the heat transfer rod 13, and the semiconductor detector body 14 is integrated, and The vacuum system was also integrated with the vacuum system of the X-ray source 17 to be detected, so that the usable vacuum region of the X-ray detector was limited. In other words, there is a possibility that organic materials such as rubber and vinyl resin may be used for the heat insulating material, the sealing material, the signal line and the power supply line 18, and 10 ^-9 Torr
In the following ultra-high vacuum region, gas is released from these substances, and therefore they cannot be used. Even if it is possible to use a structure that does not use organic matter, when evacuating to an ultra-high vacuum region, "baking out" in which the gas adsorbed on the wall of the container is detected by heating is an important process, It is impossible to bake out the semiconductor detector body 14 which must be constantly cooled with liquid nitrogen and its cooling system.

As shown by a dotted line 22 in FIG. 2, a beryllium film may be used to separate the detector side and the X-ray source 17 side into different vacuum systems, but soft X-rays with a wavelength of a few mm or more, which have a low transparency, are used. The X-ray cannot be detected because the ray cannot pass through the beryllium film.

An object of the present invention is to provide an X-ray semiconductor detector that can be used even in an ultrahigh vacuum and can detect X-rays in the soft X-ray region.

[Means for Solving the Problems] According to the present invention, the X-ray semiconductor detector main body is attached to the end of the housing and the heat transfer body inside the same vacuum system as the heat insulating bottle for liquid nitrogen. The X-ray semiconductor detector body, the housing, and the end of the heat transfer body are housed in an ultrahigh vacuum container, and the inside of the ultrahigh vacuum container is a vacuum system different from the inside of the housing.

As described above, according to the present invention, since the casing, the heat insulating bottle for liquid nitrogen, and the ultra-high vacuum container are separate vacuum systems, it is possible to use no organic substances in the vacuum system of the ultra-high vacuum container. It is easy to do, and bake-out can be performed only on the part of the ultra-high vacuum container, so it can be used in the ultra-high vacuum region, and without using a beryllium film or the like. Therefore, soft X-rays can be detected.

[Embodiment] FIG. 1 shows an embodiment of the present invention, and the portions corresponding to those in FIG. In the present invention, the housing 15
A semiconductor detector body 14 is provided at the end of the. This housing 15
Further, the ultra-vacuum container 25 is provided so that the end of the heat transfer body 13 and the semiconductor detector body 14 are built in. The ultra-vacuum container 25 is made of stainless steel, for example, and has a vacuum system different from the inside of the housing 15. The joint between the housing 15 and the ultra-vacuum container 25 is made to be able to be maintained in an ultra-high vacuum by welding or the like. The junction between the semiconductor detector main body 14 and the housing 15 is made of a heat insulating structural material 26 such as ceramic having a low thermal conductivity to minimize heat leakage. The mounting flange 16 is attached to one end of the ultra-vacuum container 25, and the gate valve 21 is also provided in the ultra-vacuum container 21. Although the liquid nitrogen supply pipe is provided as the heat transfer body 13 in this example, a heat transfer rod may be used. The ultra-vacuum container 25 is attached to the X-ray source 17 to be detected by the flange 16, and after exhausting the inside of the ultra-vacuum container 25, the gate valve 21 is opened.

"Effects of the Invention" As described above, in the present invention, the ultra-high vacuum container 25 is used, and the housing 15, and the heat insulating bottle 11 for liquid nitrogen can be provided in different vacuum systems, and the housing thereof. The signal line and the power supply line 18 can be passed through the body 15, and it is easy to prevent organic substances from existing in the ultra-high vacuum container 25.
Further, it is possible to bake out only the portion of the ultra-high vacuum container 25. Therefore, the liquid nitrogen heat insulation bottle 11 and the housing 15
It is relatively easy to make the inside vacuum system to be a vacuum necessary for heat insulation (usually about 10 ⁻⁶ Torr) and to make the inside of the ultra high vacuum container 25 to be an ultra high vacuum of 10 ⁻⁹ Torr or less. Further, it is not necessary to block it with a beryllium film or the like, X-rays from the X-ray source 17 to be detected can be directly incident on the semiconductor detector 14, and soft X-rays can be detected.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an X-ray semiconductor detector according to the present invention, and FIG. 2 is a sectional view showing a conventional X-ray semiconductor detector.

Claims (1)

[Claims] 1. A heat insulating bottle for liquid nitrogen in which liquid nitrogen is sealed, a heat transfer body connected to the heat insulating bottle for liquid nitrogen to transfer the heat of the liquid nitrogen, and a built-in heat transfer body. A housing whose inside is in the same vacuum system as the vacuum system of the heat insulating bottle for liquid nitrogen, an X-ray semiconductor detector body attached to the housing and the end of the heat transfer body, and the X-ray semiconductor detector. An X-ray semiconductor detector comprising a main body, the housing, and an end portion of a heat transfer body, and an ultrahigh vacuum container having a vacuum system different from the inside of the housing.