JP2017118428A - Method for cleaning solid-state imaging device and radiation detection apparatus - Google Patents

Abstract

A solid-state image pickup device cleaning method capable of easily removing dirt on a solid-state image pickup device. A method of cleaning a solid-state image pickup device according to the present invention is a method of cleaning a solid-state image pickup device used for cooling, and heating the solid-state image pickup device while heating the solid-state image pickup device. And a step of exhausting the gas generated by. [Selection] Figure 2

Description

  The present invention relates to a solid-state imaging element cleaning method and a radiation detection apparatus.

  There is known a technique for performing elemental analysis of a sample by irradiating the sample with a primary beam such as an electron beam or X-ray, and detecting radiation (X-ray, γ-ray, etc.) generated from the sample.

  An example is energy dispersive X-ray spectroscopy in which an electron microscope irradiates a sample with an electron microscope, detects X-rays generated from the sample, and measures the composition of the sample. In energy dispersive X-ray spectroscopy, it is utilized that characteristic X-rays have energy specific to the elements constituting the sample. In the characteristic X-ray spectrum obtained by energy dispersive X-ray spectroscopy, the element species contained in the sample is obtained from the energy value of the spectrum peak, and the content of the element species is obtained from the area of the spectrum peak. It is done.

  Another example of the above technique is an X-ray detection system using a diffraction grating and a CCD image sensor. Specifically, for example, an electron microscope irradiates the sample with an electron beam, and X-rays generated from the sample are collected by a mirror and dispersed by a diffraction grating. Then, the dispersed X-rays are received by an X-ray CCD image sensor, and a spectrum is acquired (see, for example, Patent Document 1).

JP 2012-58146 A

  In the above-described X-ray detection system, dirt may accumulate on the surface of the CCD image sensor due to measurement with high acceleration and large current, long-time measurement, frequent sample exchange, and the like. Dirt accumulated on the surface of the CCD image sensor causes a decrease in sensitivity of the CCD image sensor.

  In the above X-ray detection system, by using an unequally spaced diffraction grating, high energy resolution can be obtained, and a valence band state distribution of a portion irradiated with an electron beam can be obtained. However, if dirt is accumulated on the surface of the CCD image sensor, it becomes difficult to obtain an accurate electronic state distribution due to a decrease in sensitivity due to the accumulation of dirt.

  Therefore, the dirt accumulated on the surface of the CCD image sensor is removed by cleaning the CCD image sensor. In general, the CCD image sensor is cleaned by wiping off dirt with a solvent or the like. However, in cleaning with a solvent, the CCD image sensor must be removed from the X-ray detector, and there is a risk of disconnection of the CCD wiring or destruction of the CCD image sensor.

  The present invention has been made in view of the above problems, and one of the objects according to some aspects of the present invention is to provide a solid-state image sensor that can easily remove dirt from the solid-state image sensor. A cleaning method and a radiation detection apparatus are provided.

(1) A method for cleaning a solid-state imaging device according to the present invention includes:
A method for cleaning a solid-state imaging device used by cooling,
A step of exhausting gas generated by heating the solid-state image sensor while heating the solid-state image sensor;

  Such a method for cleaning a solid-state imaging device includes a step of exhausting the gas generated by heating the solid-state imaging device while heating the solid-state imaging device, so that dirt attached to the surface of the solid-state imaging device can be easily obtained. Can be removed. Further, according to such a method for cleaning a solid-state image sensor, the solid-state image sensor is heated to remove the dirt adhering to the surface of the solid-state image sensor. Compared with the case where it does, the possibility that a solid-state image sensor will be broken can be reduced.

(2) In the method for cleaning a solid-state imaging device according to the present invention,
In the step, the solid-state imaging device may be heated by a heating medium.

  In such a solid-state imaging device cleaning method, since the solid-state imaging device is heated by a heating medium, the solid-state imaging device can be easily and uniformly made, for example, as compared with the case where the solid-state imaging device is directly heated by contacting the solid-state imaging device. While being able to heat, the temperature of a solid-state image sensor can be raised gently. Therefore, in such a method for cleaning a solid-state image sensor, it is possible to reduce the possibility of the solid-state image sensor being broken due to a rapid temperature rise of the solid-state image sensor when the solid-state image sensor is cleaned. Further, in such a method for cleaning a solid-state image sensor, it is not necessary to arrange a heater for heating the solid-state image sensor.

(3) In the solid-state imaging device cleaning method according to the present invention,
The heating medium may be water.

  In such a solid-state imaging device cleaning method, since the solid-state imaging device is heated with water as a heating medium, the solid-state imaging device can be easily compared with a case where the solid-state imaging device is directly heated by contacting with a heater or the like. Can be heated uniformly, and the temperature of the solid-state imaging device can be gradually increased. Therefore, in such a method for cleaning a solid-state image sensor, it is possible to reduce the possibility of the solid-state image sensor being broken due to a rapid temperature rise of the solid-state image sensor when the solid-state image sensor is cleaned.

(4) In the solid-state imaging device cleaning method according to the present invention,
The temperature of the heating medium may be a temperature at which the surface temperature of the solid-state imaging device is 50 degrees or higher.

  In such a method for cleaning a solid-state image sensor, dirt attached to the surface of the solid-state image sensor can be sufficiently removed.

(5) In the solid-state imaging device cleaning method according to the present invention,
The solid-state imaging device may be a CCD image sensor or a CMOS image sensor.

(6) In the solid-state imaging device cleaning method according to the present invention,
The solid-state imaging device may constitute a radiation detector.

(7) A method for cleaning a solid-state imaging device according to the present invention includes:
In a radiation detector comprising: a solid-state imaging device that detects radiation generated from the sample by irradiating the sample with a primary line; and a cooling element for cooling the solid-state imaging device.
A method for cleaning the solid-state imaging device,
A step of exhausting gas generated by heating the solid-state image sensor while heating the solid-state image sensor;

  Such a method for cleaning a solid-state imaging device includes a step of exhausting the gas generated by heating the solid-state imaging device while heating the solid-state imaging device, so that dirt attached to the surface of the solid-state imaging device can be easily obtained. Can be removed. Further, according to such a method for cleaning a solid-state image sensor, the solid-state image sensor is heated to remove the dirt adhering to the surface of the solid-state image sensor. Compared with the case where it does, the possibility that a solid-state image sensor will be broken can be reduced.

(8) In the solid-state imaging device cleaning method according to the present invention,
During the operation of the solid-state imaging device, the cooling element is cooled by cooling the heat medium,
In the step, the solid-state imaging device may be heated by heating the heat medium.

  In such a method for cleaning a solid-state imaging device, for example, the solid-state imaging device can be cleaned in the same state as when the radiation detector is operated. Therefore, it is not necessary to adjust the radiation detector after the solid-state imaging device is cleaned.

(9) A radiation detection apparatus according to the present invention includes:
A solid-state imaging device that detects radiation generated from the sample by irradiating the sample with a primary beam;
A cooling element for cooling the solid-state imaging element;
A heat medium generating unit that selectively generates a heat medium for cooling the cooling element and a heat medium for heating the solid-state imaging element;
A cooling unit that is thermally connected to the cooling element and that cools the cooling element with a heat medium supplied from the heat medium generating unit during operation of the solid-state imaging device;
An exhaust device connected to a space in which the solid-state imaging device is disposed;
including.

  In such a radiation detection device, the heat medium generating unit generates a heating medium for heating the solid-state image sensor, and the exhaust device is connected to the space where the solid-state image sensor is arranged. The gas generated by heating the solid-state imaging device can be exhausted while heating. Therefore, in such a radiation detection apparatus, the dirt adhering to the surface of the solid-state imaging device can be easily removed.

  Further, in such a radiation detection apparatus, since the heat medium generating unit generates a cooling medium for cooling the cooling element and a heating medium for heating the solid-state imaging element, for example, when the radiation detector is in operation. The solid-state imaging device can be cleaned in the same state. Therefore, it is not necessary to adjust the radiation detector after cleaning the solid-state imaging device.

(10) In the radiation detection apparatus according to the present invention,
A control unit for controlling the heat medium generating unit;
A vacuum gauge for measuring the pressure of the space in which the solid-state imaging device is disposed;
Including
The said control part may perform control which stops the production | generation of the heat medium for heating the said solid-state image sensor to the said heat medium production | generation part based on the measurement result of the said vacuum gauge.

  In such a radiation detection apparatus, the cleaning of the solid-state imaging device can be completed at an appropriate timing.

(11) In the radiation detection apparatus according to the present invention,
A control unit for controlling the heat medium generating unit;
The control unit includes a timer for measuring time, and performs control for causing the heat medium generating unit to stop generating a heat medium for heating the solid-state imaging device when the timer measures a predetermined time. May be.

  In such a radiation detection apparatus, the cleaning of the solid-state imaging device can be completed at an appropriate timing.

The figure which shows typically the X-ray detection system which concerns on 1st Embodiment. The figure which shows typically the cleaning process of the solid-state image sensor which concerns on 1st Embodiment. The figure which shows typically the cleaning process of the solid-state image sensor which concerns on 2nd Embodiment. The figure which shows typically the X-ray detection system which concerns on 3rd Embodiment. The figure which shows typically the cleaning process of the solid-state image sensor which concerns on 3rd Embodiment. The figure which shows typically the X-ray detection system which concerns on 4th Embodiment. The figure which shows typically the cleaning process of the solid-state image sensor which concerns on 4th Embodiment. The figure which shows typically the X-ray detection system which concerns on 5th Embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are essential constituent requirements of the present invention.

  In the following, as a method for cleaning a solid-state image pickup device according to the present invention, a method for cleaning a solid-state image pickup device of an X-ray detector mounted on an X-ray detection system will be described as an example. In addition, the cleaning method of the solid-state imaging device according to the present invention is not limited to this example, and can be applied to a solid-state imaging device that is used after being cooled.

  Hereinafter, an X-ray detection system including an X-ray detector that detects X-rays will be described as an example of the radiation detection apparatus according to the present invention. However, the radiation detection apparatus according to the present invention is an X-ray detection system. It may be a radiation detection system provided with a radiation detector that detects other radiation (γ rays or the like).

1. 1. First embodiment 1.1. X-ray Detection System First, an X-ray detection system (an example of a radiation detection apparatus) according to a first embodiment will be described with reference to the drawings. FIG. 1 is a diagram schematically illustrating an X-ray detection system 100 according to the first embodiment. 1 illustrates a state in which the X-ray detector 40 is operating in the X-ray detection system 100, that is, a state in which the X-ray detector 40 is cooled and X-ray detection is possible. Show.

  As shown in FIG. 1, the X-ray detection system 100 includes an electron beam irradiation unit 10, an X-ray condensing mirror unit 20, a diffraction grating 30, an X-ray detector 40 (an example of a radiation detector), and a chiller. 50 and the exhaust device 60.

The electron beam irradiation unit 10 includes an electron gun as an electron beam source of a scanning electron microscope (SEM) and an irradiation lens system. The electron beam irradiation unit 10 irradiates the sample S with an electron beam. The X-ray detection system 100 has a function as a scanning electron microscope for acquiring a scanning electron microscope image, for example.

  The X-ray condensing mirror unit 20 condenses the characteristic X-rays emitted from the sample S and guides them to the diffraction grating 30. By condensing the characteristic X-rays with the X-ray condenser mirror unit 20, the intensity of the characteristic X-rays incident on the diffraction grating 30 can be increased. Thereby, the measurement time can be shortened and the S / N ratio of the spectrum can be improved.

  The X-ray condensing mirror unit 20 includes, for example, two mirrors facing each other. The distance between the two mirrors is narrow on the sample S side (incident side) and wide on the diffraction grating 30 side (exit side). Thereby, compared with the case where there is no X-ray condensing mirror part 20, the intensity | strength of the characteristic X-ray which injects into the diffraction grating 30 can be increased.

  The diffraction grating 30 receives characteristic X-rays collected by the X-ray condenser mirror unit 20 and generates diffracted X-rays having different diffraction states according to energy. The diffraction grating 30 is a non-uniformly spaced diffraction grating in which irregularly spaced grooves are formed for aberration correction. The diffraction grating 30 is configured to form the focal point of the diffracted X-ray on the light receiving surface 43 of the solid-state image sensor 42 instead of on the Roland circle when the characteristic X-ray is incident at a large incident angle.

  The X-ray detector 40 detects diffracted X-rays. The X-ray detector 40 includes a solid-state image sensor 42, a cooling element 44, a cooling unit 46, and an image sensor control unit 48.

  The solid-state image sensor 42 detects diffracted X-rays. The solid-state image sensor 42 is a solid-state image sensor having high sensitivity to soft X-rays.

  The solid-state image sensor 42 is, for example, a CCD (Charge-Coupled Device) image sensor, a CMOS (Complementary MOS) image sensor, or the like. The solid-state image sensor 42 is, for example, a back-illuminated CCD image sensor (or a CMOS image sensor).

  The position of the solid-state image sensor 42 is adjusted so that the light receiving surface 43 coincides with the image plane of diffracted X-rays.

  The cooling element 44 cools the solid-state imaging element 42. The solid-state image sensor 42 is cooled to, for example, about −70 degrees by the cooling element 44. Thereby, the solid-state image sensor 42 can be detected with high sensitivity. The cooling element 44 is, for example, a Peltier element.

  The cooling unit 46 cools the cooling element 44. For example, the cooling unit 46 cools the heat dissipation unit of the Peltier element. The cooling unit 46 is supplied with cold water F2 (an example of a cooling medium) having a predetermined temperature (for example, 20 degrees) from the chiller 50. The cooling unit 46 cools the cooling element 44 (a heat dissipation part of the Peltier element) with the cold water F2.

  In the illustrated example, the cooling unit 46 and the chiller 50 are connected by a pipe 52. By connecting the chiller 50 and the cooling unit 46 with the pipe 52, the cold water F2 can be circulated between the chiller 50 and the cooling unit 46. Since the cooling unit 46 is thermally connected to the cooling element 44 (a heat dissipation part of the Peltier element), the cooling element 44 can be cooled by circulating the cold water F2.

The image sensor control unit 48 controls the solid-state image sensor 42 and the cooling element 44. The image sensor control unit 48 supplies power to the solid-state image sensor 42 and the cooling element 44. Further, the image sensor control unit 48 performs processing for outputting the output signal of the solid-state image sensor 42 to the outside (for example, a waveform analyzer).

  The chiller 50 cools water as a heat medium to generate cold water F2. The chiller 50 supplies the cold water F2 to the cooling unit 46 while keeping the cold water F2 at a constant temperature. The chiller 50 circulates cold water F <b> 2 with the cooling unit 46.

  The cold water F2 is 20 degree water, for example. Note that the temperature of the cold water F <b> 2 can be appropriately set according to the temperature of the cooling element 44.

  The chiller 50 is connected to the cooling unit 46 through a pipe 52. The chiller 50 supplies cold water F <b> 2 to the cooling unit 46 when the solid-state image sensor 42 is in operation. The chiller 50 can circulate the cold water F <b> 2 with the cooling unit 46.

  In addition, although the example which cools the cooling element 44 with the cold water F2 was demonstrated here, the cooling medium for cooling the cooling element 44 should just be a fluid which can cool the cooling element 44, and oil Alternatively, gas or the like may be used.

  The exhaust device 60 is connected to the inside (space) of the sample chamber 12 in which the sample S, the X-ray condensing mirror unit 20, the diffraction grating 30, and the X-ray detector 40 are arranged. The exhaust device 60 exhausts the sample chamber 12. Thereby, the sample chamber 12 can be made into the pressure reduction state. The exhaust device 60 is, for example, a turbo molecular pump, an oil diffusion pump, an ion pump, or the like.

  Although not shown, the X-ray detection system 100 analyzes the diffracted X-rays that are diffracted by the diffraction grating 30 and detected by the solid-state imaging device 42, and indicates the number of X-rays detected for each energy. You may comprise including the waveform analyzer which produces | generates a distribution spectrum. Further, the X-ray detection system 100 may include a display unit (display) that displays an energy distribution spectrum generated by the waveform analyzer.

  1.2. A method for cleaning a solid-state imaging device.

  Next, a cleaning method for the solid-state imaging device according to the first embodiment will be described with reference to the drawings.

  FIG. 2 is a diagram schematically illustrating a cleaning process of the solid-state imaging device according to the first embodiment.

  First, as shown in FIG. 2, the X-ray detector 40 is removed from the housing of the X-ray detection system 100. Then, the solid-state imaging element 42 is hermetically sealed by the vacuum sealing flange 2. The space sealed by the vacuum sealing flange 2 is evacuated (evacuated) by the exhaust device 4 through the vacuum pipe 3. At this time, the supply of power to the image sensor control unit 48 is stopped. The exhaust device 4 is, for example, an oil rotary pump, a scroll pump, a turbo molecular pump, or the like.

  Next, the pipe 6 is connected to the cooling unit 46 of the X-ray detector 40 and the hot water circulation device 8 is attached. The hot water circulation device 8 heats water as a heat medium to generate hot water F4 (an example of a heating medium). The hot water circulation device 8 supplies the hot water F4 to the cooling unit 46 while keeping the hot water F4 at a constant temperature. The hot water circulation device 8 circulates the hot water F4 with the cooling unit 46.

  Next, the solid-state image sensor 42 is heated. The solid-state image sensor 42 is heated by the hot water F4. As shown in FIG. 2, the hot water circulating device (for example, a chiller) 8 circulates the hot water F4 between the hot water circulating device 8 and the cooling unit 46 to heat the solid-state imaging element 42.

  By heating the solid-state image sensor 42, dirt attached to the surface (light receiving surface 43) of the solid-state image sensor 42 is released as a gas. The released gas (dirt) is exhausted by the exhaust device 4. In this way, the dirt attached to the surface of the solid-state image sensor 42 can be removed by exhausting the gas generated by heating the solid-state image sensor 42 while heating the solid-state image sensor 42.

  At this time, the surface temperature of the solid-state imaging element 42 needs to be set to, for example, 50 degrees or more. When the surface temperature of the solid-state image sensor 42 is lower than 50 degrees, dirt (such as hydrocarbon) attached to the surface of the solid-state image sensor 42 cannot be sufficiently removed. The temperature of the hot water F4 needs to be set to a temperature several degrees higher than the desired surface temperature of the solid-state image sensor 42 in consideration of the temperature exchange efficiency. The higher the surface temperature of the solid-state image sensor 42 and the temperature of the hot water F4, the higher the removal efficiency of the surface of the solid-state image sensor 42. However, when the surface temperature of the solid-state image sensor 42 exceeds the heat-resistant temperature of the solid-state image sensor 42, The possibility that the solid-state image sensor 42 is broken becomes extremely high. Therefore, the temperature of the hot water F4 needs to be set to a temperature at which the surface temperature of the solid-state image sensor 42 is equal to or lower than the heat-resistant temperature of the solid-state image sensor 42. The temperature of the hot water F4 is, for example, not less than 50 degrees and not more than 90 degrees.

  Moreover, it is desirable to raise the temperature of the hot water F4 gently. Thereby, since the temperature of the solid-state image sensor 42 can be gradually raised, the possibility that the solid-state image sensor 42 is broken due to the rapid temperature rise of the solid-state image sensor 42 can be reduced.

  The dirt accumulated on the surface of the solid-state image sensor 42 can be removed by performing a process for exhausting the gas generated by heating the solid-state image sensor 42 for a predetermined time while heating the solid-state image sensor 42.

  The solid-state imaging element 42 can be cleaned through the above steps.

  After the cleaning of the solid-state image sensor 42 is completed, the X-ray detector 40 is mounted on the housing of the X-ray detection system 100 as shown in FIG. 1, and the light-receiving surface 43 of the solid-state image sensor 42 has diffraction X-rays. The position is adjusted so as to coincide with the image plane.

  In the above-described embodiment, as shown in FIG. 2, an exhaust system is configured by the vacuum sealing flange 2, the vacuum pipe 3, and the exhaust device 4, and the gas generated by heating the solid-state imaging element 42 is exhausted. did. On the other hand, although not shown, for example, when the X-ray detection system 100 includes an exhaust system that exhausts the solid-state imaging element 42 separately from the exhaust system that exhausts the electron beam irradiation unit 10 and the sample chamber 12. The solid-state imaging device 42 may be cleaned using the exhaust system while the X-ray detector 40 is mounted on the X-ray detection system 100.

  The solid-state imaging device cleaning method according to the first embodiment has the following features, for example.

The solid-state imaging device cleaning method according to the first embodiment includes a step of exhausting the gas generated by heating the solid-state imaging device 42 while heating the solid-state imaging device 42. For this reason, dirt attached to the surface of the solid-state imaging element 42 can be removed. In addition, according to the method for cleaning a solid-state image sensor according to the first embodiment, the surface of the solid-state image sensor 42 is removed with, for example, a solvent in order to remove the dirt attached to the surface of the solid-state image sensor 42 by heating the solid-state image sensor 42. Compared with the case of removing dirt adhering to the solid-state image sensor, it is not necessary to remove the solid-state image sensor 42 from the X-ray detector 40, and the possibility that the solid-state image sensor 42 is broken can be reduced. Therefore, the dirt adhering to the surface of the solid-state image sensor 42 can be easily removed.

  In the solid-state image sensor cleaning method according to the first embodiment, the solid-state image sensor 42 is heated with water as a heating medium. As described above, in the solid-state imaging device cleaning method according to the first embodiment, since the solid-state imaging device 42 is heated via the heating medium, for example, the solid-state imaging device 42 is directly heated by contacting a heater or the like. In comparison, the solid-state image sensor 42 can be easily heated uniformly, and the temperature of the solid-state image sensor 42 can be gradually increased. Therefore, it is possible to reduce the possibility that the solid-state image sensor 42 is broken due to a rapid temperature rise of the solid-state image sensor 42 during cleaning.

  In the solid-state imaging device cleaning method according to the first embodiment, the temperature of the heating medium (water) is a temperature at which the surface temperature of the solid-state imaging device 42 is 50 degrees or more. Therefore, according to the method for cleaning a solid-state imaging device according to the first embodiment, as described above, dirt attached to the surface of the solid-state imaging device 42 can be sufficiently removed.

  In the method for cleaning a solid-state imaging device according to the first embodiment, as shown in FIG. 2, dirt (which is released by heating of the solid-state imaging device 42 in a state where the solid-state imaging device 42 is sealed by the vacuum sealing flange 2). Gas). Therefore, the dirt can be prevented from adhering to the wall portion of the sample chamber 12, the piping of the X-ray detection system 100, and the like.

2. Second Embodiment 2.1. X-ray Detection System Next, an X-ray detection system according to the second embodiment will be described. The configuration of the X-ray detection system according to the second embodiment is the same as the configuration of the X-ray detection system 100 according to the first embodiment shown in FIG.

  In the X-ray detection system according to the second embodiment, the chiller 50 is configured to cool and heat water as a heat medium, and can selectively generate cold water F2 and hot water F4. That is, the chiller 50 functions as a heat medium generating unit that generates a cooling medium (cool water F2) for cooling the cooling element 44 and a heating medium (warm water F4) for heating the solid-state imaging element 42.

  Therefore, in the X-ray detection system according to the second embodiment, when the X-ray detector 40 shown in FIG. 1 is operating (a state in which X-ray detection is possible), the chiller 50 supplies water as a heat medium. The cooling element 44 is cooled by cooling to the cold water F2 and supplying the cold water F2 to the cooling unit 46. Further, when cleaning the solid-state image sensor 42 described later (see FIG. 3), the water as a heat medium is heated by the chiller 50 to form hot water F4, and the hot water F4 is supplied to the cooling unit 46 to thereby obtain the solid-state image sensor. 42 is heated.

  2.2. A method for cleaning a solid-state imaging device.

  Next, a method for cleaning a solid-state imaging device according to the second embodiment will be described with reference to the drawings. FIG. 3 is a diagram schematically illustrating a cleaning process of the solid-state imaging device according to the second embodiment.

As shown in FIG. 3, water as a heat medium is heated by a chiller 50. For example, when the user operates the chiller 50 to specify the temperature of the water, the chiller 50 is moved to the cold water F2 (for example, 20
Water is heated to F4 having a specified temperature (for example, a temperature at which the surface temperature of the solid-state imaging device 42 is 50 degrees or more). As a result, the hot water F4 circulates between the cooling unit 46 and the chiller 50 via the pipe 52, and the solid-state imaging element 42 is heated. At this time, the exhaust device 60 is operating and exhausting the sample chamber 12. Therefore, the gas generated by heating the solid-state image sensor 42 is exhausted.

  The chiller 50 gradually increases the temperature of the cold water F2 to obtain hot water F4. Thereby, it is possible to reduce the possibility that the solid-state image sensor 42 is broken due to the rapid temperature rise of the solid-state image sensor 42.

  The dirt accumulated on the surface of the solid-state image sensor 42 can be removed by performing a process for exhausting the gas generated by heating the solid-state image sensor 42 for a predetermined time while heating the solid-state image sensor 42.

  The solid-state imaging element 42 can be cleaned through the above steps.

  When the user operates the chiller 50 and designates the temperature of the water after the cleaning of the solid-state image sensor 42 is completed, the chiller 50 cools the hot water F4 and the cold water F2 having the designated temperature (for example, 20 degrees). (See FIG. 1). Thereby, the cooling element 44 is cooled, and the solid-state imaging element 42 can be brought into an operable state (a state where X-ray detection is possible).

  The solid-state imaging device cleaning method according to the second embodiment has the following features, for example.

  In the solid-state image sensor cleaning method according to the second embodiment, the solid-state image sensor 42 is heated while the solid-state image sensor 42 is heated, as in the solid-state image sensor cleaning method according to the first embodiment described above. Since it includes the step of exhausting the generated gas, the solid-state imaging element 42 can be easily removed.

  Further, in the solid-state imaging device cleaning method according to the second embodiment, when the solid-state imaging device 42 is operated, the cooling device 44 is cooled by cooling water as a heat medium, and the solid-state imaging device 42 is heated. The solid-state image sensor 42 is heated by heating water as a heat medium. Therefore, in the solid-state imaging device cleaning method according to the second embodiment, the solid-state imaging device 42 can be cleaned without removing the X-ray detector 40 from the housing of the X-ray detection system. That is, the solid-state image sensor 42 can be cleaned in the same state as when the X-ray detector 40 is operating. Therefore, according to the method for cleaning a solid-state imaging device according to the second embodiment, adjustment of the X-ray detector 40 (for example, adjustment of the light receiving surface 43 of the solid-state imaging device 42) becomes unnecessary after the solid-state imaging device 42 is cleaned.

3. Third Embodiment 3.1. X-ray Detection System Next, an X-ray detection system according to a third embodiment will be described with reference to the drawings. FIG. 4 is a diagram schematically illustrating an X-ray detection system 300 according to the third embodiment. FIG. 4 illustrates a state in which the X-ray detector 40 is operating in the X-ray detection system 300.

  Hereinafter, in the X-ray detection system 300 according to the third embodiment, members having the same functions as those of the constituent members of the X-ray detection system 100 according to the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof are given. Omitted.

  As shown in FIG. 4, the X-ray detection system 300 includes an electron beam irradiation unit 10, an X-ray collector mirror unit 20, a diffraction grating 30, an X-ray detector 40, a chiller 50, and an exhaust device 60. The vacuum gauge 70 and the control unit 80 are included.

  In the X-ray detection system 300, similarly to the X-ray detection system according to the second embodiment described above, the chiller 50 is configured to cool and heat water as a heat medium, and cools the cooling element 44. It functions as a heat medium generating unit that generates a cooling medium (cold water F2) for heating and a heating medium (hot water F4) for heating the solid-state imaging device 42.

  The vacuum gauge 70 measures the pressure in the space (sample chamber 12) in which the solid-state image sensor 42 is disposed. The vacuum gauge 70 is, for example, a Pirani vacuum gauge or a Penning vacuum gauge.

  The control unit 80 controls the chiller 50. For example, the control unit 80 controls the temperature of water as a heat medium by controlling the chiller 50. Details of the processing of the control unit 80 will be described in “3.2. Cleaning method of solid-state imaging device” described later.

  The function of the control unit 80 may be realized by executing a program by a processor (CPU, DSP, etc.), or may be realized by a dedicated circuit such as an ASIC (gate array, etc.).

  The X-ray detection system 300 includes an operation unit (not shown). The operation unit performs a process of acquiring an operation signal corresponding to an operation by the user and sending it to the control unit 80. The operation unit is, for example, a button, a key, a touch panel type display, or the like.

  3.2. A method for cleaning a solid-state imaging device.

  Next, a method for cleaning a solid-state imaging device according to the third embodiment will be described with reference to the drawings. FIG. 5 is a diagram schematically illustrating a cleaning process of the solid-state imaging device according to the third embodiment.

  For example, when the user requests the start of cleaning of the solid-state image sensor 42 via the operation unit, the control unit 80 starts processing for cleaning the solid-state image sensor 42 based on an operation signal from the operation unit.

  First, the control unit 80 controls the chiller 50 to heat water so that water as a heat medium has a preset temperature (for example, a temperature at which the surface temperature of the solid-state imaging element 42 is 50 degrees or more). I do. Thereby, the chiller 50 circulates the hot water F4 between the cooling part 46 and the chiller 50, and the solid-state image sensor 42 is heated. At this time, the exhaust device 60 is operating and exhausting the sample chamber 12. Therefore, the gas generated by heating the solid-state image sensor 42 is exhausted.

  Here, since gas is generated by heating the solid-state imaging device 42, the pressure in the sample chamber 12 is higher than the pressure in the sample chamber 12 when the X-ray detector 40 is operated, for example (degree of vacuum). Becomes lower). When the cleaning progresses and the dirt accumulated on the surface of the solid-state image sensor 42 decreases, the pressure in the sample chamber 12 decreases (the degree of vacuum increases).

Therefore, the control unit 80 monitors the measurement result of the vacuum gauge 70, and controls the chiller 50 to stop heating water based on the measurement result of the vacuum gauge 70, that is, heat for heating the solid-state imaging device 42. Control to stop media generation. More specifically, the control unit 80 monitors the measurement result of the vacuum gauge 70, and the pressure in the sample chamber 12 is equal to or lower than a predetermined pressure (for example, lower than the pressure in the sample chamber 12 when the X-ray detector 40 is operated). When it becomes, control which makes the chiller 50 stop heating of water is performed. Thereby, the chiller 50 stops heating of water.

  The solid-state imaging element 42 can be cleaned through the above steps.

  Control part 80 performs control which stops water so that warm water F4 (water) may become predetermined temperature (for example, 20 degrees) to chiller 50, after performing control which stops heating of warm water F4. Thereby, the chiller 50 circulates the cold water F2 between the cooling part 46 and the chiller 50, and the cooling element 44 is cooled. Therefore, the solid-state imaging element 42 can be brought into an operable state (a state in which X-ray detection is possible).

  The X-ray detection system 300 according to the third embodiment has the following features, for example.

  The X-ray detection system 300 according to the third embodiment generates a cooling medium (cold water F2) for the chiller 50 to cool the cooling element 44 and a heating medium (hot water F4) for heating the solid-state imaging element 42. Therefore, the solid-state imaging device 42 can be cleaned without removing the X-ray detector 40 from the housing of the X-ray detection system, and adjustment of the X-ray detector 40 is not required after the solid-state imaging device 42 is cleaned. .

  In the X-ray detection system 300 according to the third embodiment, the control unit 80 controls the chiller 50 to stop generating a heat medium for heating the solid-state imaging device 42 based on the measurement result of the vacuum gauge 70. (Control to stop heating of water). Therefore, in the X-ray detection system 300, the cleaning of the solid-state imaging device can be completed at an appropriate timing. Further, in the X-ray detection system 300, the cleaning of the solid-state imaging device 42 can be automatically ended, so that it is possible to save time and effort for ending the cleaning.

4). Fourth embodiment 4.1. X-ray Detection System Next, an X-ray detection system according to a fourth embodiment will be described with reference to the drawings. FIG. 6 is a diagram schematically illustrating an X-ray detection system 400 according to the fourth embodiment. FIG. 6 illustrates a state in which the X-ray detector 40 is operating in the X-ray detection system 400.

  Hereinafter, in the X-ray detection system 400 according to the fourth embodiment, the members having the same functions as the constituent members of the X-ray detection system 100 according to the first embodiment and the X-ray detection system 300 according to the third embodiment. The same reference numerals are assigned and detailed description thereof is omitted.

  As shown in FIG. 6, the X-ray detection system 400 includes an electron beam irradiation unit 10, an X-ray collector mirror unit 20, a diffraction grating 30, an X-ray detector 40, a chiller 50, and an exhaust device 60. , And the control unit 80.

  In the X-ray detection system 400, the chiller 50 is configured to be able to cool and heat water as a heat medium, similar to the X-ray detection system 300 described above, and a cooling medium for cooling the cooling element 44. It functions as a heat medium generating unit that generates a heating medium (warm water F4) for heating the (cold water F2) and the solid-state imaging device 42.

  The control unit 80 controls the chiller 50. For example, the control unit 80 controls the temperature of water as a heat medium by controlling the chiller 50. The control unit 80 includes a timer 82 that measures time. Details of the processing of the control unit 80 will be described in “4.2. Cleaning method of solid-state imaging device” described later.

  4.2. A method for cleaning a solid-state imaging device.

  Next, a method for cleaning a solid-state imaging device according to the fourth embodiment will be described with reference to the drawings. FIG. 7 is a diagram schematically illustrating a cleaning process of the solid-state imaging device according to the fourth embodiment.

  For example, when the user requests the start of cleaning of the solid-state image sensor 42 via the operation unit, the control unit 80 starts processing for cleaning the solid-state image sensor 42 based on an operation signal from the operation unit.

  First, the control unit 80 performs control to heat the chiller 50 so that water as a heat medium has a preset temperature. Thereby, the chiller 50 circulates the hot water F4 between the cooling part 46 and the chiller 50, and the solid-state image sensor 42 is heated. At this time, the exhaust device 60 is operating and exhausting the sample chamber 12. Therefore, the gas generated by heating the solid-state image sensor 42 is exhausted.

  Further, the control unit 80 starts measuring time by the timer 82 in response to a request to start cleaning (that is, based on an operation signal). Then, when the timer 82 measures a predetermined time, the control unit 80 performs control to cause the chiller 50 to stop heating water, that is, control to stop generation of a heat medium for heating the solid-state imaging element 42. . Thereby, the chiller 50 stops heating of water. The predetermined time measured by the timer 82 is, for example, an arbitrary time set in advance.

  The solid-state imaging element 42 can be cleaned through the above steps.

  Control part 80 performs control which stops water so that warm water F4 (water) may become predetermined temperature (for example, 20 degrees) to chiller 50, after performing control which stops heating of warm water F4. As a result, the solid-state imaging element 42 can be brought into an operable state (a state in which X-ray detection is possible).

  The X-ray detection system 400 according to the fourth embodiment has the following features, for example.

  The X-ray detection system 400 according to the fourth embodiment generates a cooling medium (cold water F2) for the chiller 50 to cool the cooling element 44 and a heating medium (hot water F4) for heating the solid-state imaging element 42. To do. Therefore, in the X-ray detection system 400, the solid-state imaging element 42 can be cleaned without removing the X-ray detector 40 from the housing of the X-ray detection system, similarly to the X-ray detection system 300 described above. Adjustment of the X-ray detector 40 becomes unnecessary after the image sensor 42 is cleaned.

  In the X-ray detection system 400 according to the fourth embodiment, the control unit 80 includes a timer 82, and heat for heating the solid-state imaging device 42 to the chiller 50 when the timer 82 measures a predetermined time. Control to stop the production of the medium (control to stop heating the water) is performed. Therefore, in the X-ray detection system 400, the cleaning of the solid-state imaging device can be finished at an appropriate timing. Further, in the X-ray detection system 400, the cleaning of the solid-state imaging device 42 can be automatically ended, so that it is possible to save time and effort for ending the cleaning.

5. Fifth embodiment 5.1. X-ray Detection System Next, an X-ray detection system according to a fifth embodiment will be described with reference to the drawings. FIG. 8 is a diagram schematically illustrating an X-ray detection system 500 according to the fifth embodiment. FIG. 8 illustrates a state in which the X-ray detector 40 is operating in the X-ray detection system 500.

  Hereinafter, in the X-ray detection system 500 according to the fifth embodiment, the members having the same functions as the constituent members of the X-ray detection system 100 according to the first embodiment and the X-ray detection system 300 according to the third embodiment. The same reference numerals are assigned and detailed description thereof is omitted.

  As shown in FIG. 8, the X-ray detection system 500 includes an electron beam irradiation unit 10, an X-ray condensing mirror unit 20, a diffraction grating 30, an X-ray detector 40, a chiller 50, and an exhaust device 60. The vacuum gauge 70 and the control unit 80 are included.

  In the X-ray detection system 500, the control unit 80 controls the chiller 50 and the X-ray detector 40. In the X-ray detection system 500, for example, when the user adds a command for cleaning the solid-state imaging device 42 after the continuous measurement sequence in the control software executed by the control unit 80, the control unit 80 performs X-rays according to the command. After the continuous measurement is performed in the detector 40, a process for cleaning the solid-state imaging device 42 is started.

  The process of cleaning the solid-state image sensor 42 by the control unit 80 is the same as the above-described “3.2. Cleaning method of the solid-state image sensor” or “4.2. Cleaning method of the solid-state image sensor”. Is omitted.

  Further, the control unit 80 may perform a process of stopping the supply of power to the image sensor control unit 48 of the X-ray detector 40 in the process of cleaning the solid-state image sensor 42.

  Note that the control unit 80 may measure the total measurement time of the X-ray detector 40 and start the process of cleaning the solid-state imaging device 42 when the total measurement time is equal to or longer than a predetermined time. In addition, when the total measurement time exceeds a predetermined time, the control unit 80 displays warning information on a display unit (a display or the like, not shown) in order to prompt the user to clean the solid-state image sensor 42. Processing, processing for lighting a warning lamp (not shown), or the like may be performed.

  In addition, the control unit 80 may measure the operation time (cooling time) of the solid-state image sensor 42 and start a process of cleaning the solid-state image sensor 42 when the operation time reaches a predetermined time or more. . Further, the control unit 80 may perform the process for prompting the user to clean the solid-state imaging element 42 when the operation time becomes equal to or longer than a predetermined time.

  In addition, the control unit 80 may monitor the measurement result of the vacuum gauge 70 and perform a process of recording the history of the pressure (vacuum degree) in the sample chamber 12. And the control part 80 performs the process which cleans the solid-state image sensor 42, when the frequency | count of the pressure rise (decrease in a vacuum degree) of the sample chamber 12 during the operation | movement period of the solid-state image sensor 42 becomes more than predetermined number. May start. In addition, the control unit 80 performs the above-described process for prompting the user to clean the solid-state image sensor 42 when the number of times the pressure in the sample chamber 12 increases during the operation period of the solid-state image sensor 42 becomes equal to or greater than a predetermined number. May be performed.

In addition, the control unit 80 may monitor the measurement result of the vacuum gauge 70 and perform a process of recording the history of the pressure (vacuum degree) in the sample chamber 12. Then, the control unit 80 starts a process of cleaning the solid-state image sensor 42 when the time during which the pressure of the sample chamber 12 during the operation period of the solid-state image sensor 42 is equal to or higher than a predetermined pressure is equal to or longer than a predetermined time. May be. In addition, the control unit 80
Even if the above-described process is performed to prompt the user to clean the solid-state image sensor 42 when the time during which the pressure in the sample chamber 12 has exceeded the predetermined pressure during the operation period of the solid-state image sensor 42 has exceeded a predetermined time. Good.

  The X-ray detection system 500 according to the fifth embodiment has the following features, for example.

  Since the X-ray detection system 500 according to the fifth embodiment can periodically clean the solid-state imaging device 42 as described above, the solid-state imaging device can be cleaned at an appropriate timing. Dirt accumulated on the surface of the image sensor 42 can be reduced. Further, in the X-ray detection system 500, as described above, it is possible to prompt the user to periodically clean the solid-state image sensor 42. Therefore, the solid-state image sensor can be cleaned at an appropriate timing.

  In the X-ray detection system 500 according to the fifth embodiment, as described above, the solid-state image sensor 42 can be cleaned based on the history of the pressure (vacuum degree) in the sample chamber 12. Compared with the case where the cleaning is performed based on the operation time of 42, the solid-state imaging element 42 can be cleaned at a more appropriate timing.

  This is because, for example, when a sample S with a large amount of degassing is introduced into the sample chamber 12, even if the operation time of the solid-state image sensor 42 is short, the dirt adhering to the surface of the solid-state image sensor 42 may increase. Because.

  In the X-ray detection system 500 according to the fifth embodiment, as described above, the user can be urged to clean the solid-state imaging device 42 based on the history of the pressure (vacuum degree) in the sample chamber 12. Therefore, the solid-state image sensor 42 can be cleaned at a more appropriate timing.

  In addition, this invention is not limited to embodiment mentioned above, A various deformation | transformation implementation is possible within the range of the summary of this invention.

  For example, in the above-described embodiment, the case where the solid-state image sensor 42 is heated by a heating medium such as the hot water F4 in the cleaning of the solid-state image sensor 42 has been described. However, for example, the direct current supplied to the Peltier element as the cooling element 44 The solid-state image sensor 42 may be heated by reversing the polarity of the current from the state when the solid-state image sensor 42 is being cooled. Thus, by reversing the polarity of the direct current supplied to the Peltier element, the cooling side and the heat dissipation side of the Peltier element are reversed, and the solid-state imaging element 42 can be heated.

  For example, in the above-described embodiment, the example in which the X-ray detector 40 detects X-rays generated from the sample S by irradiating the sample S with the electron beam has been described. The line is not limited to an electron beam, and may be, for example, an X-ray or an ion.

  In addition, embodiment mentioned above and a modification are examples, Comprising: It is not necessarily limited to these. For example, each embodiment and each modification can be combined as appropriate.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

2 ... Vacuum sealing flange, 3 ... Vacuum piping, 4 ... Exhaust device, 6 ... Piping, 8 ... Hot water circulation device, 10 ... Electron beam irradiation unit, 12 ... Sample chamber, 20 ... X-ray focusing mirror unit, 30 ... Diffraction grating, 40 ... X-ray detector, 42 ... Solid-state imaging device, 43 ... Light receiving surface, 44 ... Cooling device, 46 ... Cooling unit, 48 ... Image sensor control unit, 50 ... Chiller, 52 ... Piping, 60 ... Exhaust device , 70 ... Vacuum gauge, 80 ... Control unit, 82 ... Timer, 100 ... X-ray detection system, 300 ... X-ray detection system, 400 ... X-ray detection system, 500 ... X-ray detection system

Claims (11)

A method for cleaning a solid-state imaging device used by cooling,
A method for cleaning a solid-state imaging device, comprising a step of exhausting a gas generated by heating the solid-state imaging device while heating the solid-state imaging device. In claim 1,
In the step, the solid-state imaging device cleaning method, wherein the solid-state imaging device is heated by a heating medium. In claim 2,
The method for cleaning a solid-state imaging device, wherein the heating medium is water. In claim 2 or 3,
The method for cleaning a solid-state imaging device, wherein the temperature of the heating medium is a temperature at which the surface temperature of the solid-state imaging device is set to 50 degrees or more. In any one of Claims 1 thru | or 4,
The solid-state imaging device is a CCD image sensor or a CMOS image sensor. In any one of Claims 1 thru | or 5,
The method for cleaning a solid-state image sensor, wherein the solid-state image sensor constitutes a radiation detector. Cleaning of the solid-state imaging device in a radiation detector comprising: a solid-state imaging device that detects radiation generated from the sample by irradiating the sample with a primary line; and a cooling device for cooling the solid-state imaging device A method,
A method for cleaning a solid-state imaging device, comprising a step of exhausting a gas generated by heating the solid-state imaging device while heating the solid-state imaging device. In claim 7,
During the operation of the solid-state imaging device, the cooling element is cooled by cooling the heat medium,
In the step, the solid-state image sensor cleaning method, wherein the solid-state image sensor is heated by heating the heat medium. A solid-state imaging device that detects radiation generated from the sample by irradiating the sample with a primary beam;
A cooling element for cooling the solid-state imaging element;
A heat medium generating unit that selectively generates a heat medium for cooling the cooling element and a heat medium for heating the solid-state imaging element;
A cooling unit that is thermally connected to the cooling element and that cools the cooling element with a heat medium supplied from the heat medium generating unit during operation of the solid-state imaging device;
An exhaust device connected to a space in which the solid-state imaging device is disposed;
A radiation detection device. In claim 9,
A control unit for controlling the heat medium generating unit;
A vacuum gauge for measuring the pressure of the space in which the solid-state imaging device is disposed;
Including
The said control part is a radiation detection apparatus which performs control which stops the production | generation of the thermal medium for heating the said solid-state image sensor to the said thermal medium production | generation part based on the measurement result of the said vacuum gauge. In claim 9,
A control unit for controlling the heat medium generating unit;
The control unit includes a timer for measuring time, and controls the heat medium generation unit to stop generating a heat medium for heating the solid-state imaging device when the timer measures a predetermined time. , Radiation detector.

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