JP3479231B2 - Discharge-resistant microstrip gas chamber using auxiliary anode wiring - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge-breakdown-type microstrip gas chamber using auxiliary anode wiring, and more particularly to a microstrip gas chamber (MS
The present invention relates to an electrode for preventing anode disconnection of GC).

[0002]

2. Description of the Related Art MSGC is a new type of gas-amplified particle beam detector having high position resolution and time resolution, which was first described in A. Suggested by Oed. Further, the inventors of the present application have proposed this detector as an image detector by making it two-dimensional. As a feature of this detector, in addition to high position resolution, it is pointed out that the gas amplifier has an extremely short dead time, and there are great expectations as a detector for a high-intensity particle beam. Currently X
Tested with wire every second, 10 ⁷ per square mm
It has been confirmed that there is no hindrance to the operation even under the brightness above the count.

As a high-gain gas radiation detector of this kind, Japanese Patent Application No. 10-8 has already been proposed by the present inventors.
9750 (Patent No. 2843319).

FIG. 4 shows such a conventional gas radiation detector (M
FIG. 5 is an exploded perspective view of the SGC), and FIG. 5 is a block diagram showing the overall configuration of the data collection system of the gas radiation detector (MSGC).

In FIG. 4, the MSGC 102, which is a two-dimensional image device, comprises a substrate 1, an anode strip 2 and a cathode strip 3, and the anode strips 2 and the cathode strips 3 are arranged alternately.

[0006] Further, it has a base substrate 4 and a back strip 5 formed on the base substrate 4 and located below the substrate 1.

Further, the element 10 thus formed
A drift plate 6 is disposed above the substrate 2 at a distance D _{1 of} about 1 cm from the substrate 1 to form a chamber in which a gas containing argon and ethane flows, for example. In addition, 7
Is an amplifier.

Further, as shown in FIG.
01 includes a two-dimensional MSGC (hereinafter, simply referred to as MSGC) 102, preamplifiers / wave height discriminators 103 and 104,
A preamplifier 105 is mounted.

Further, a first signal synchronization circuit 111 for processing an output signal from the anode of the MSGC 102, MSGC1.
A second signal synchronization circuit 112 for processing an output signal from the back electrode (back strip) of No. 02, a first encoder 113 connected to the first signal synchronization circuit 111, and a second signal synchronization circuit 112. A second encoder 114, an incident particle beam hit determination circuit 115, a large-capacity storage device 116, and a computer 117, which are connected to, form a data collection system.

The cathode of the MSGC 102 is a preamplifier 105-analog-digital converter (ADC) 10
6 to the mass storage device 116.

[0011]

[Problems to be Solved by the Invention] However, MSG
One of the biggest problems in putting C into practical use is destruction of electrodes due to discharge between electrodes. 5 in MSGC
When a high voltage is applied to obtain a high gas amplification factor because a voltage is applied between electrodes with a spacing of 0 μm or less, a large current flows between the electrodes and the heat generated by the discharge cuts the electrode strip or fragments thereof. There was a frequent occurrence of obstacles for electrical continuity between the electrodes due to, for example, adherence to the surface insulating layer.

When one part of the anode strip was cut by the discharge, the region from that part along the anode to the part on the opposite side of the read pad was completely dead.

Most of the causes of this discharge are caused by the defect of the pattern of the electrode strip and the adhesion of dust. Therefore, efforts are made to remove this defect by high quality control. It is difficult to create a pattern over a large area without defects in the conventional I
It was very difficult because it did not exist in C / LSI manufacturing technology.

As described above, when dealing with the problem of discharge of MSGC, conventionally, the emphasis was placed on how to prevent the occurrence of discharge, but if the idea is changed and discharge occurs, However, it is only necessary to finally obtain the necessary signal.

In order to solve the above problems, the present invention provides
It is an object of the present invention to provide a discharge resistant breakdown type microstrip gas chamber using an auxiliary anode wiring capable of reading a signal even if discharge breakdown occurs.

[0016]

In order to achieve the above object, the present invention provides [1] a discharge-breakdown-resistant microstrip gas chamber using auxiliary anode wiring, which is connected to both ends of an anode strip. The first and second terminals and the auxiliary anode wiring connected to the first electrode via the second terminal are provided.

[2] A discharge-resistant breakdown type microstrip gas chamber using the auxiliary anode wiring as described in [1] above, wherein the material of the anode strip is a high melting point conductor.

Therefore, if the signal is read out at both ends of the anode strip, even if discharge breakdown occurs at only one place, the dead region is partially discharged (typically) due to the signal read before and after that. It can be suppressed to only several tens of μm). This size is usually smaller than the position resolution of MSGC, and has almost no influence on the imaging ability.

As a conventional influence of discharge breakdown, there is often a case where the anode and the cathode are electrically connected, but in order to prevent this, by mounting a very high melting point substance as the material of the strip. In addition, the conductive material that scatters in the vicinity of the occurrence of electric discharge is made as small as possible, and rather, the method of actively cutting the defective portion is adopted.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic view of a main part of a discharge-breakdown-type microstrip gas chamber using auxiliary anode wiring according to an embodiment of the present invention, and FIG. 2 is an anode / cathode showing an embodiment of the present invention.
It is a figure which shows the material of the pole strip.

In this figure, 200 is the substrate, 201 is the anode strip, 202 is the first terminal of the anode strip, 203 is the second terminal (auxiliary terminal) of the anode strip, 204 is the first interlayer via, and 205 is Auxiliary anode electrode (back strip), 206 is second interlayer via, 207
Is a bonding wire, 208 is a lead pad, 209 is a cathode strip, and 210 is a back strip.

As described above, in order to realize reading from both ends of the anode strip 201, the substrate (insulating layer) 20
0, an auxiliary anode electrode 205 is arranged in a position parallel to the anode strip 201, and both ends of the anode strip 201 are connected by interlayer vias 204 and 206.

The material of the anode strip 201 / cathode strip 209 on the surface is changed from the conventional gold having a thickness of 1 μm to a conductor having a high melting point of 0.2 μm, for example, chrome / palladium. A high melting point and a low amount of substance during discharge have been realized.

Therefore, as shown in FIG. 2, the strips 201 and 209 have a higher melting point than that of conventional gold, and when discharging, they are easily cut and the metal is less likely to scatter, so that the amount of the substance is small. , The upper layer is a palladium (Pd) layer 20
2B, and the lower layer was made of a chromium (Cr) layer 202A.

The results of the operation test of the discharge-proof breakdown type microstrip gas chamber using the auxiliary anode wiring of the present invention will be described.

In FIG. 1, for example, the anode strip 2
When a disconnection occurs at the point A of 01, conventionally, the left side of the disconnected point A becomes a dead area and the particle beam cannot be measured. However, according to the present invention, the left side of the disconnected point A Also in the portion, when the particle beam enters, the second terminal (auxiliary terminal) 203 of the anode strip 201, the first interlayer via 204, the auxiliary anode electrode (back strip) 20
5, the particle beam can be measured through the second interlayer via 206 and the first terminal 202 of the anode strip 201.

Further, it is difficult to numerically show the effect of the present invention because the number of samples produced is limited, but as a rule of thumb, the portion which becomes a dead region due to discharge breakdown is 1/4. Reduced to

FIG. 3 is a view showing a measurement state by the discharge-resistant breakdown type microstrip gas chamber of the present invention.
In this figure, the white part is the region where X-rays can be detected, and the black part is the dead region.

In the anode strip line indicated by the arrow in FIG. 3, a disconnection occurs at points A and B. In this case, only the central part I is a dead zone, and both sides are dead. The II part and the III part are regions where X-rays are detected.

As described above, according to FIG. 3, it is understood that the particle beam can be measured when the particle beam enters even in the two parts on the right side of the broken point A and on the left side of the broken point B.

The present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and these modifications are not excluded from the scope of the present invention.

[0033]

As described in detail above, according to the present invention, the following effects can be achieved.

(A) By using the auxiliary anode wiring,
The signal can be read even if the discharge breakdown of the anode strip occurs.

(B) The material of the anode / cathode wiring can be changed to a thin conductor, for example, chrome / palladium, to realize a high melting point of the strip and a low substance amount at the time of discharge.

[Brief description of drawings]

FIG. 1 is a schematic view of a main portion of a discharge-breakdown-resistant microstrip gas chamber using an auxiliary anode wire according to an embodiment of the present invention.

FIG. 2 is a view showing materials of anode / cathode strips showing an embodiment of the present invention.

FIG. 3 is a view showing a dead region of a strip formed by the discharge-resistant breakdown type microstrip gas chamber of the present invention.

FIG. 4 is an exploded perspective view of a conventional gas radiation detector (MSGC).

FIG. 5 is a block diagram showing an overall configuration of a conventional data collection system for a gas radiation detector (MSGC).

[Explanation of symbols]

200 substrates 201 anode strip 202 First terminal of anode strip 202A Chrome (Cr) layer (lower layer) 202B conductor [palladium (Pd) layer (upper layer)] 203 Second terminal of anode strip (auxiliary terminal) 204 First interlayer via 205 Auxiliary anode electrode (back strip) 206 Second interlayer via 207 Bonding wire 208 Derived Putt 209 cathode strip 210 backstrip

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-10-300856 (JP, A) JP-A-8-201524 (JP, A) JP-A-9-243753 (JP, A) JP-A-11- 45680 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G01T 1/167

Claims (2)

(57) [Claims] 1. A discharge-breakdown-type microstrip gas chamber using auxiliary anode wiring, comprising: (a) first and second ends connected to both ends of an anode strip.
And (b) an auxiliary anode wiring connected to the first terminal via the second terminal, and a discharge breakdown resistant type using the auxiliary anode wiring. Microstrip gas chamber. 2. A discharge-withstand breakdown microstrip gas chamber with the auxiliary anode wire of claim 1, wherein the material of the anode strips, the auxiliary anode wires, characterized by comprising a conductor having a high melting point Discharge-resistant microstrip gas chamber using.