JP2000214264A - Anti-discharge breakdown type microstrip gas chamber using auxiliary anode wiring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-discharge breakdown type microstrip gas chamber using an auxiliary anode wiring capable of signal reading even in occurrence of a discharge breakdown. SOLUTION: The anti-discharge breakdown type microstrip gas chamber using an auxiliary anode wiring is provided with a first and a second terminals 202 and 203 connected to both ends of an anode strip 201 and an auxiliary anode path [the second terminal (auxiliary terminal) 203 of the anode strip-first intra-layer via 204-auxiliary node (back side strip) 205-second intra-layer via 206] connected to the first terminal 202 by way of the second terminal 203. With this constitution, if a particle beam comes in, measurement of the particle beam is possible also in the left side part of the break of wire point A by way of the second terminal (auxiliary terminal) 203 of the anode strip 201, first intra-layer via 204, auxiliary node (back side strip) 205, second intra-layer via 206 and the first terminal 202 of the anode strip 201.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge breakdown resistant microstrip gas chamber using an auxiliary anode wiring, and more particularly to an electrode for anodic cutting of a microstrip gas chamber (MSGC).

[0002]

2. Description of the Related Art In 1988, MSGC was proposed as a new type of gas-amplified particle beam detector having high position resolution and time resolution. Proposed by Oed. Further, the inventors of the present application have made this detector two-dimensional and have proposed it as an image detector. As a feature of this detector, in addition to the high positional resolution, it is mentioned that the dead time is extremely short as a gas amplifier, and there is great expectation as a detector for a particle beam with high brightness. Currently X
In the test using the wire, 10 ⁷ per square mm per second
It has been confirmed that there is no problem in operation even at a brightness higher than the count.

A high-gain gas radiation detector of this type is disclosed in Japanese Patent Application No. Hei 10-8 already proposed by the present inventors.
No. 9750 (Japanese Patent No. 2843319).

FIG. 4 shows such a conventional gas radiation detector (M).
FIG. 5 is a block diagram showing an overall configuration of a data acquisition system of the gas radiation detector (MSGC).

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

[0006] Further, it has a base substrate 4 and a backstrip 5 formed on the base substrate 4 and positioned below the substrate 1.

Further, the element 10 thus formed is
The second upper drift plate 6 is arranged at a distance D ₁ of the approximately 1cm from the substrate 1, for example, a chamber of a gas consisting of argon and ethane flows are formed. Note that 7
Is an amplifier.

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

A first signal synchronizing circuit 111 for processing an output signal from the anode of the MSGC 102,
02, a second signal synchronization circuit 112 for processing an output signal from the back electrode (backstrip), a first encoder 113 connected to the first signal synchronization circuit 111, and a second signal synchronization circuit 112. , A data collection system is constructed by the second encoder 114 connected thereto, the incident particle beam hit determination circuit 115, the mass storage device 116, and the computer 117.

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

[0011]

SUMMARY OF THE INVENTION However, MSG
One of the biggest difficulties in putting C to practical use is the destruction of electrodes due to discharge between the electrodes. In MSGC, 5
When a high voltage is applied to obtain a high gas amplification rate because a voltage is applied between the electrodes at an interval of 0 μm or less, a large current due to discharge flows between the electrodes, and the electrode strip is cut by heat generated by the discharge, or a fragment thereof For example, a failure that causes conduction between the electrodes occurs frequently, for example, by adhering to the surface insulating layer.

When one part of the anode strip is cut by the discharge, the area from the part along the anode to the part on the opposite side of the readout pad is completely insensitive.

Most of the causes of the discharge are caused by defects in the pattern of the electrode strip and adhesion of dust. Efforts have been made to eliminate the defects by advanced quality control. Producing a pattern over such a large area without defects is a problem with the conventional I
It was very difficult because it did not exist in the C / LSI manufacturing technology and the like.

As described above, when dealing with the problem of MSGC discharge, conventionally, the emphasis has been placed on how to prevent a discharge from occurring. However, it is only necessary that a necessary signal is finally obtained.

The present invention has been made in order to solve the above problems.
An object of the present invention is to provide an anti-discharge breakdown type microstrip gas chamber using an auxiliary anode wiring which enables signal reading even if a discharge breakdown occurs.

[0016]

According to the present invention, there is provided a discharge-resistant microstrip gas chamber using auxiliary anode wiring, which is connected to both ends of an anode strip. It has a first and a second terminal, and an auxiliary anode path connected to the first electrode via the second terminal.

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

Therefore, by performing signal reading at both ends of the anode strip, even if discharge breakdown occurs only at one location, reading of the signal from before and after that causes the dead area to become a part of the discharge breakdown (typically). (Approximately several tens of μm). This size is usually smaller than the position resolution of MSGC, and hardly affects the imaging ability.

In addition, as a result of the conventional discharge breakdown, conduction between the anode and the cathode has often been observed. To prevent this, a very high-melting-point material is mounted as a material for the strip. In addition, a method is adopted in which the conductive material that scatters in the vicinity when a discharge occurs is reduced as much as possible, and rather, a method of actively cutting a defective portion is adopted.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a main part of a discharge-resistant microstrip gas chamber using an auxiliary anode wiring according to an embodiment of the present invention, and FIG. 2 is a view showing a material of an anode / cathode strip according to an embodiment of the present invention. FIG.

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

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

The material of the anode strip 201 and the cathode strip 209 on the surface is changed from a conventional 1 μm thick gold to a 0.2 μ thick high melting point conductor, for example, chromium / palladium. High melting point and low amount of substance during discharge are realized.

Therefore, as shown in FIG. 2, the strips 201 and 209 have a higher melting point than the conventional gold, and are easy to cut when discharging, for example, having a low material amount which is hard to be scattered. , The upper layer is a palladium (Pd) layer 20
2B, a lower layer made of a chromium (Cr) layer 202A.

The results of an operation test of a discharge breakdown resistant 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 is an insensitive area and measurement of the particle beam cannot be performed. Also, 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 (backside strip) 20
5. Particle beam measurement can be performed via 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 manufactured samples is limited. However, as a rough guide, a portion which becomes a dead area due to discharge breakdown is 1/4. Decreased to below.

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

In the anode strip line marked with an arrow in FIG. 3, disconnection occurs at points A and B. In this case, only a part I at the center is a dead area and both sides are insensitive. Portions II and III are regions where X-rays are detected.

Thus, it can be seen from FIG. 3 that the particle beam can be measured at the two portions on the right side of the broken point A and on the left side of the broken point B when the particle beam enters.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0033]

As described above, according to the present invention, the following effects can be obtained.

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

(B) The material of the anode / cathode wiring is changed to a conductor having a small thickness, for example, chromium / palladium,
It is possible to realize a high melting point of the strip and a low substance amount at the time of discharge.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part of a discharge-resistant microstrip gas chamber using an auxiliary anode wiring according to an embodiment of the present invention.

FIG. 2 is a view showing a material of an anode / cathode strip according to an embodiment of the present invention.

FIG. 3 is a view showing a dead zone of a strip by the 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 the overall configuration of a conventional data acquisition system for a gas radiation detector (MSGC).

[Explanation of symbols]

 Reference Signs List 200 substrate 201 anode strip 202 first terminal of anode strip 202A chromium (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 (backside strip) 206 second interlayer via 207 bonding wire 208 lead-out pad 209 cathode strip 210 backstrip

Claims (2)

[Claims] 1. A discharge-resistant microstrip gas chamber using auxiliary anode wiring, comprising: (a) first and second terminals connected to both ends of an anode strip; and (b) said second terminal. A discharge-resistant microstrip gas chamber using an auxiliary anode wiring, comprising: an auxiliary anode path connected to the first terminal via a terminal. 2. A discharge-resistant microstrip gas chamber using an auxiliary anode wiring according to claim 1, wherein a material of said anode strip is made of a conductor having a high melting point. A discharge-resistant microstrip gas chamber using a.