Bayonet wear detection device and semiconductor equipment

Abstract

The utility model provides a bayonet lock wear detection device and semiconductor equipment. The bayonet lock wear detection device comprises a signal transmitter and a signal receiver, the signal transmitter is positioned above or below the bayonet lock and is used for transmitting a detection signal to the bayonet lock; the signal receiver is used for receiving a detection signal penetrating through the bayonet lock so as to obtain the abrasion condition of the bayonet lock according to the detection signal. According to the utility model, the signal transmitter transmits the signal to the bayonet lock, the signal passes through the bayonet lock and is received by the signal receiver, and the wear condition of the bayonet lock can be obtained according to the obtained detection signal, so that the bayonet lock can be replaced in time, the quality of a finished wafer is prevented from being influenced, and the detection efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor equipment, in particular to a latch wear detection device and semiconductor equipment. Background Art

[0002] When chemically etching wafers, existing etching machines usually use multiple pins to clamp the wafers. However, during use, friction will occur between the wafer and the pins, and the pins will wear under the side pressure of the wafer. As the amount of goods running increases, the wear of the pins will increase. Especially during the back-end process, most of the process will thin the wafer by about 100um. The thinning of the wafer will increase the wear of the pins and even damage the pins, and even cause the pins to be cut off. Moreover, in this process, the residual acid on the front side of the wafer will also increase, reducing the product appearance yield, and in severe cases, causing wafer fragments.

[0003] At present, the wear condition of the latch pin is usually detected by manually touching or visually observing the wear condition of the latch pin during daily inspection and equipment maintenance, or by inferring the wear condition of the latch pin based on the product appearance. The current manual detection method has low detection efficiency and cannot detect the wear condition of the latch pin in time, which affects the product appearance yield.

[0004] In view of this, it is necessary to provide a latch wear detection device and a semiconductor device to solve the above problems. Utility Model Content

[0005] The utility model aims to provide a latch pin wear detection device and semiconductor equipment, so as to improve the problem that the existing manual detection method has low detection efficiency and cannot detect the latch pin wear in time.

[0006] The utility model provides a device for detecting wear of a bayonet pin, comprising: a signal transmitter and a signal receiver; the signal transmitter is located above or below the bayonet pin and is used for transmitting a detection signal to the bayonet pin; the signal receiver is used for receiving the detection signal passing through the bayonet pin, so as to obtain the wear condition of the bayonet pin according to the detection signal.

[0007] In a possible embodiment, the detent pins are divided into several groups, each group of the detent pins has at least two pins, and the several groups of the detent pins are arranged on the chuck at intervals along the circumferential direction of the chuck; each group of the detent pins is provided with a driving mechanism, and the driving mechanism is used to drive the corresponding group of the detent pins to adjust the position so as to replace the detent pins in the group that are located in the position of clamping the wafer.

[0008] In a possible embodiment, the driving mechanism includes an inner ring gear, a sun gear, at least two planetary gears, a motor and a planetary bracket, the inner ring gear is arranged on the chuck, the sun gear is arranged concentrically with the inner ring gear, the motor is drivingly connected to the sun gear, the planetary gears are respectively meshingly connected with the inner ring gear and the sun gear, and the planetary bracket is provided with an axle corresponding to each of the planetary gears, and the planetary gear sleeve is arranged on the axle; the pin is detachably mounted on the upper part of the axle and is located at the edge of the driving mechanism; the side of the pin that clamps the wafer protrudes from the periphery of the driving mechanism, or the component on the driving mechanism that passes the detection signal is made of a material that can pass the detection signal.

[0009] In a possible embodiment, the detection device further includes a bearing seat disposed on the upper portion of the shaft, the bayonet is detachably mounted on the bearing seat, and the bearing seat is made of a material that can pass the detection signal.

[0010] In a possible embodiment, a group of the signal transmitter and the signal receiver is correspondingly provided for each of the pins located at the wafer clamping position, each of the signal transmitter includes at least one signal transmitter head, and each of the signal receiver includes at least one signal receiver head.

[0011] In a possible embodiment, the signal transmitter is embedded in the top surface of the chuck, and the signal receiver is disposed at the top of the process chamber; or, the signal transmitter is disposed at the top of the process chamber, and the signal receiver is embedded in the top surface of the chuck; or, the chuck is hollow inside, the signal transmitter is disposed inside the chuck, and the signal receiver is disposed at the top of the process chamber; or, the chuck is hollow inside, the signal transmitter is disposed at the top of the process chamber, and the signal receiver is disposed inside the chuck.

[0012] In a possible embodiment, the latch portion protrudes from the periphery of the driving mechanism and forms a clamping portion for clamping the wafer, and the transmitting head of the signal transmitter and the receiving head of the signal receiver are arranged corresponding to the clamping portion.

[0013] In a possible embodiment, the detection device also includes a controller; the controller is controlled and connected to the signal receiver and the driving mechanism, and the controller is used to calculate the wear value of the pin based on the detection data of the detection signal, and when it is detected that the pin located at the wafer clamping position reaches a preset wear value, the controller controls the corresponding driving mechanism to replace the pin located at the wafer clamping position; and / or, the controller is controlled and connected to an alarm mechanism, and the alarm mechanism is used to generate an alarm signal.

[0014] In a possible embodiment, the signal transmitter is a laser transmitter, and the signal receiver is a laser receiver; or, the signal transmitter is an infrared transmitter, and the signal receiver is an infrared receiver.

[0015] In a possible embodiment, the connection line between the signal receiver and the signal transmitter is located on the side of the wafer clamped by the pin.

[0016] The utility model also provides a semiconductor device, comprising: a chuck, a plurality of chuck pins arranged at intervals along the circumferential direction of the chuck, and a chuck pin wear detection device as described in any one of the above embodiments.

[0017] The beneficial effects of the pin wear detection device and semiconductor equipment provided by the utility model are: the signal transmitter transmits a signal toward the pin, the signal passes through the pin, and is received by the signal receiver. The wear condition of the pin can be obtained according to the obtained detection signal, so as to replace the pin in time and avoid affecting the quality of the finished wafer, while also improving the detection efficiency. In a further scheme, a group of pins are set corresponding to each wafer clamping position to rotate the wafer, and the sun gear is driven to rotate by the motor, driving the planetary gear to move along the circumferential direction of the inner ring gear, thereby moving and adjusting the position of a group of pins, and moving the unworn pins to the wafer clamping position, thereby realizing automatic replacement of the pins. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the latch pin wear detection device of the present utility model.

[0019] Figure 2 It is a schematic diagram of the driving mechanism in the latch wear detection device of the present utility model.

[0020] Figure 3 This is a schematic diagram of the bayonet, bearing seat and driving mechanism of the bayonet wear detection device of the utility model in the first embodiment.

[0021] Figure 4 It is a schematic diagram of the bayonet pin, the bearing seat and the driving mechanism of the bayonet pin wear detection device of the utility model in the second embodiment.

[0022] Figure 5 It is a schematic diagram of the bayonet pin, the bearing seat and the driving mechanism of the bayonet pin wear detection device of the utility model in the third embodiment.

[0023] Figure 6 It is a schematic diagram of the latch pin, the bearing seat and the driving mechanism of the latch pin wear detection device in the fourth embodiment of the utility model.

[0024] Explanation of the reference numerals: signal transmitter 110; signal receiver 120; driving mechanism 130; inner ring gear 131; sun gear 132; planetary gear 133; motor 134; planetary bracket 135; shaft 136; bearing seat 140; slot 141; controller 150; alarm mechanism 160; pin 200; clamping portion 210; chuck 300; mounting slot 301; sealing plate 320; wafer 400; process chamber 500. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the utility model clearer, the technical solution in the embodiments of the utility model will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] In view of the problems existing in the prior art, the embodiment of the present utility model provides a wear detection device for a bayonet pin 200, see Figure 1 and Figure 3 The detection device includes a signal transmitter 110 and a signal receiver 120. The signal transmitter 110 is located above or below the bayonet 200 and is used to transmit a detection signal to the bayonet 200. The signal receiver 120 is used to receive the detection signal passing through the bayonet 200, so as to obtain the wear condition of the bayonet 200 according to the detection signal. Preferably, the bayonet 200 is made of a material that can pass the detection signal, such as polyketone.

[0027] In this embodiment, a signal transmitter 110 and a signal receiver 120 are provided corresponding to the bayonet pin 200. The signal transmitter 110 transmits a detection signal to the bayonet pin 200, and the detection signal can pass through the bayonet pin 200. The signal receiver 120 receives the detection signal that passes through the bayonet pin 200, and generates a signal spectrum according to the acquired detection signal. By analyzing and calculating the signal spectrum, the wear condition of the bayonet pin 200 can be obtained. When the bayonet pin 200 is worn, a notch is generated on the bayonet pin 200, and the wafer 400 partially extends into the notch, or the acid liquid penetrates into the notch. In addition to passing through the bayonet pin 200, the signal will also pass through the wafer 400 and the acid liquid. The position and shape of the absorption peak in the signal spectrum, the peak intensity and the relative intensity and other parameter information will change. By setting the threshold range of the relevant parameters in the signal spectrum, the wear degree of the bayonet pin 200 can be judged. It should be noted that different substances will show specific absorption peaks in the signal spectrum, and the position of the absorption peak is related to the chemical bonds and functional groups in the substance. By analyzing the position of the absorption peak, the possible types of chemical bonds or functional groups in the substance can be preliminarily determined, and the composition of the substance can be inferred. At the same time, the shape of the absorption peak can also provide information about the molecular vibration mode and possible intermolecular interactions. The peak intensity reflects the vibration intensity of a specific chemical bond or functional group in the substance, while the relative intensity compares the size relationship between different absorption peaks. These parameters can provide information about the proportion and concentration of different components in the substance, which helps to determine the composition and structure of the substance. Therefore, according to the changes in the relevant parameters of the signal spectrum, the position of the wafer 400 can be calibrated and the wear of the pin 200 can be quantified to determine the degree of wear of the pin 200, and the relative position of the wafer 400 and the pin 200 can be monitored during the reaction.

[0028] In a preferred embodiment, see Figure 1 and Figure 3 The clamping pins 200 are divided into several groups, each group of clamping pins 200 has at least two clamping pins, and the several groups of clamping pins 200 are arranged on the chuck 300 at intervals along the circumferential direction of the chuck 300. Each group of clamping pins 200 is provided with a driving mechanism 130, and the driving mechanism 130 is used to drive the corresponding group of clamping pins 200 to adjust the position, so as to replace the clamping pins 200 in the group located at the position of clamping the wafer 400.

[0029] In the prior art, several latch pins 200 are usually arranged at intervals along the circumferential direction of the chuck 300. When a latch pin 200 is detected to be worn, it is usually necessary to stop the machine, open the process chamber 500, and then replace the latch pin 200. Each time a latch pin 200 is worn, the machine must be stopped once. Frequent shutdowns reduce the machine production time. In this embodiment, a group of latch pins 200 is set for each wafer 400 clamping position. When the latch pin 200 in the group located at the wafer 400 clamping position is worn, the group of latch pins 200 is driven by the driving mechanism 130 to adjust the position, and the unworn latch pin 200 is rotated to the wafer 400 clamping position to replace the latch pin 200 currently located at the wafer 400 clamping position, thereby realizing automatic replacement of the latch pin 200 without frequent shutdowns and frequent opening of the process chamber 500, thereby improving the machine production efficiency.

[0030] See also Figure 2 and Figure 3 The driving mechanism 130 includes an inner gear ring 131, a sun gear 132, at least two planetary gears 133, a motor 134 and a planetary support 135. The inner gear ring 131 is arranged on the chuck 300, the sun gear 132 is arranged concentrically with the inner gear ring 131, the motor 134 is drivingly connected to the sun gear 132, the planetary gears 133 are respectively meshed with the inner gear ring 131 and the sun gear, at least two planetary gears 133 are spaced apart along the inner gear ring 131, and a shaft 136 is provided on the planetary support 135 corresponding to each planetary gear 133, and the planetary gear 133 is sleeved on the shaft 136. The bayonet 200 is detachably mounted on the upper part of the shaft 136 and is located at the edge of the driving mechanism 130. In the first embodiment, see Figure 3 , the side of the wafer 400 held by the latch 200 protrudes from the periphery of the driving mechanism 130 so that the transmission path of the detection signal avoids the driving mechanism 130, or, in the second embodiment, see Figure 4 , the component on the driving mechanism 130 through which the detection signal passes is made of a material that can pass through the detection signal, for example, transparent hard organic materials such as PC (polycarbonate) and PTFE (polytetrafluoroethylene) are used to avoid affecting the transmission of the detection signal. The bayonet 200 is arranged in a one-to-one correspondence with the planetary gear 133. In this embodiment, the driving mechanism 130 adopts a planetary gear structure, and the motor 134 drives the sun gear 132 to rotate, driving the planetary gear 133 to rotate around the corresponding shaft 136. At the same time, the planetary gear 133 moves along the inner wall of the inner gear ring 131 with the shaft 136 thereon, thereby realizing the position adjustment of the bayonet 200, that is, the bayonet 200 can be moved and adjusted along the circumferential direction of the inner gear ring 131, realizing the automatic replacement of the bayonet 200.

[0031] In the third embodiment, see Figure 2 and Figure 5The detection device further comprises a bearing seat 140 disposed on the upper part of the shaft 136, and the bayonet 200 is detachably mounted on the bearing seat 140, and the bearing seat 140 is made of a material that can pass the detection signal. Specifically, a card slot 141 is provided on the top surface of the bearing seat 140, and the bottom end of the bayonet 200 is clamped in the card slot 141. By providing the bearing seat 140, the bayonet 200 can be stably supported and fixed, and the bayonet 200 can be conveniently disassembled and installed. Preferably, a mounting groove 301 is provided on the top surface of the chuck 300, and the driving mechanism 130 is disposed in the mounting groove 301. A sealing plate 320 is sealed at the notch of the mounting groove 301. The sealing plate 320 is provided with an annular slide groove, and the extension direction of the slide groove is consistent with the moving trajectory of the shaft 136. The shaft 136 passes through the slide groove on the sealing plate 320, and the upper part of the shaft 136 extends out of the sealing plate 320 to install the bearing seat 140.

[0032] In a preferred embodiment, see Figure 1 , a group of signal transmitters 110 and signal receivers 120 are correspondingly arranged for each bayonet 200 located at a position for clamping a wafer 400, each signal transmitter 110 includes at least one signal transmitter head, each signal receiver 120 includes at least one signal receiver head, and the signal transmitter head and the signal receiver head are arranged toward the corresponding bayonet 200 located at a position for clamping a wafer 400. On the one hand, by arranging a signal transmitter 110 and a signal receiver 120 for each bayonet 200, the wear condition of the bayonet 200 at each wafer 400 clamping position can be obtained separately, so as to replace each bayonet 200 at a wafer 400 clamping position separately. On the other hand, a plurality of signal transmitter heads and a plurality of signal receiver heads are correspondingly arranged for each bayonet 200 located at a position for clamping a wafer 400, so as to perform detection from multiple positions, thereby increasing the accuracy and timeliness of detection.

[0033] In some possible embodiments, see Figure 1 , the signal transmitter 110 is embedded in the top surface of the chuck 300, and the signal receiver 120 is disposed at the top of the process chamber 500; or, the signal transmitter 110 is disposed at the top of the process chamber 500, and the signal receiver 120 is embedded in the top surface of the chuck 300; or, the chuck 300 is hollow inside, the signal transmitter 110 is disposed in the chuck 300, and the signal receiver 120 is disposed at the top of the process chamber 500; or, the chuck 300 is hollow inside, the signal transmitter 110 is disposed at the top of the process chamber 500, and the signal receiver 120 is disposed in the chuck 300. In this embodiment, the method of being embedded in the top surface of the chuck 300 allows the signal transmitter 110 and the signal receiver 120 to be directly aligned with the bayonet pin 200, thereby preventing the signal from passing through other components such as the chuck 300, and improving the accuracy of signal analysis. The method of being arranged inside the chuck 300 facilitates retrofit installation on the existing chuck 300 , and the chuck 300 can protect the signal transmitter 110 and the signal receiver 120 .

[0034] In another specific embodiment, see Figure 1 and Figure 6 The latch 200 partially protrudes from the periphery of the driving mechanism 130 and forms a clamping portion 210 for clamping the wafer 400. The transmitting head of the signal transmitter 110 and the receiving head of the signal receiver 120 are arranged corresponding to the clamping portion 210 so that the signal passes through the clamping portion 210. In this embodiment, the clamping portion 210 protrudes from the periphery of the driving mechanism 130 so that the signal can avoid the driving mechanism 130 to avoid interference with the signal.

[0035] In one possible embodiment, see Figure 1 The detection device also includes a controller 150, which is connected to the signal receiver 120 and the drive mechanism 130. The controller 150 is used to calculate the wear value of the latch pin 200 according to the detection data of the detection signal. When the latch pin 200 located at the position of the wafer 400 is detected to reach the preset wear value, the corresponding drive mechanism 130 is controlled to replace the latch pin 200 located at the position of the wafer 400. And / or, the controller 150 is controlled to be connected to an alarm mechanism 160, which is used to generate an alarm signal, and the alarm mechanism 160 includes an alarm light and / or an alarm speaker. Preferably, the controller 150 is connected to the semiconductor production system to realize the card control of the number of wafers 400 running away. In this embodiment, the controller 150 calculates the wear value of the latch pin 200 according to the detection data of the detection signal. When the latch pin 200 that needs to be replaced is detected, after the current process step is completed, the controller 150 controls the corresponding drive mechanism 130 to replace the worn latch pin 200 located at the position of the wafer 400. In addition, the alarm mechanism 160 can promptly remind engineers to check the current wear condition of the latch pins 200. When a group of latch pins 200 are all in a worn state, it is necessary to stop the machine and replace the entire group of latch pins 200. This realizes automated detection and reminders, improves detection accuracy and efficiency, eliminates the need for frequent shutdowns, and improves production efficiency.

[0036] In some possible embodiments, the signal transmitter 110 is a laser transmitter and the signal receiver 120 is a laser receiver; or, the signal transmitter 110 is an infrared transmitter and the signal receiver 120 is an infrared receiver, but not limited thereto. The housing of the signal transmitter 110 and the housing of the signal receiver 120 are made of acid-resistant material.

[0037] Preferably, the connection line between the signal receiver 120 and the signal transmitter 110 is located on the side of the pin 200 that clamps the wafer 400. The side of the pin 200 that clamps the wafer 400 can be understood as the part between the center line of the pin 200 and the side of the pin 200 close to the wafer 400, so as to more accurately detect the wear of the part of the pin 200 that clamps the wafer 400.

[0038] The wear detection device for the latch pin 200 and the semiconductor device of the utility model propose a technical solution for automated wear detection of the latch pin 200 and replacement of the latch pin 200. The signal transmitter 110 transmits a signal toward the latch pin 200, and the signal passes through the latch pin 200 and is received by the signal receiver 120. When the latch pin 200 is worn, the signal spectrum will also change. By analyzing and processing the signal spectrum, the wear degree of the latch pin 200 can be calculated and judged, and the engineer can be promptly issued with an early warning of residual acid, broken pieces and equipment maintenance, so as to avoid the increase of residual acid on the front side of the wafer 400 due to the damage of the latch pin 200, the reduction of the product appearance yield, and the fragmentation of the wafer 400. The wear detection device for the latch pin 200 can monitor the wear degree of the latch pin 200 in real time without stopping the machine or performing other additional detection steps. In addition, the existing installation method of the latch pin is usually that a single latch pin 200 is installed independently, which means that each time the latch pin 200 is replaced, the process chamber 500 needs to be shut down and opened. In this solution, a group of pins 200 are loaded corresponding to each position of the wafer 400 for clamping to achieve rotation clamping. The controller 150 controls the driving mechanism 130 to adjust the position of a group of pins 200 to replace the worn pins 200, without the need to frequently stop the machine and open the process chamber 500 to replace the pins 200, which can extend the production time of the machine and improve production efficiency.

[0039] Although the embodiments of the utility model are described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes are within the scope and spirit of the utility model in the claims. Moreover, the utility model described herein may have other embodiments and may be implemented or realized in a variety of ways. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with ordinary skills in the field to which the utility model belongs. The words "including" and the like used herein mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

Claims

1. A device for detecting wear of a latch pin, characterized in that: include: Signal transmitter and signal receiver; The signal transmitter is located above or below the latch and is used to transmit a detection signal to the latch; The signal receiver is used to receive a detection signal passing through the latch pin, so as to obtain the wear condition of the latch pin according to the detection signal.

2. The detent wear detection device according to claim 1, characterized in that: The bayonet pins are arranged in a plurality of groups, each group of the bayonet pins has at least two bayonet pins, and the bayonet pins in the plurality of groups are arranged on the chuck at intervals along the circumferential direction of the chuck; Each group of the latches is provided with a driving mechanism, and the driving mechanism is used to drive the corresponding group of the latches to adjust their positions so as to replace the latches in the group that are located at the wafer clamping position.

3. The detent wear detection device according to claim 2, characterized in that: The driving mechanism comprises an inner gear ring, a sun gear, at least two planetary gears, a motor and a planetary support, wherein the inner gear ring is arranged on the chuck, the sun gear is arranged concentrically with the inner gear ring, the motor is drivingly connected with the sun gear, the planetary gears are respectively meshed with the inner gear ring and the sun gear, a shaft rod is provided on the planetary support corresponding to each of the planetary gears, the planetary gears are sleeved on the shaft rod, and the bayonet pin is detachably mounted on the upper part of the shaft rod and is located at the edge of the driving mechanism; The side of the wafer clamped by the pin protrudes from the periphery of the driving mechanism, or the component of the driving mechanism through which the detection signal passes is made of a material that can pass the detection signal.

4. The detent wear detection device according to claim 3, characterized in that: It also includes a bearing seat arranged on the upper part of the shaft rod, the bayonet is detachably mounted on the bearing seat, and the bearing seat is made of a material that can pass the detection signal.

5. The detent wear detection device according to claim 2, characterized in that: A group of the signal transmitter and the signal receiver is correspondingly arranged for each of the latches located at the wafer clamping position, each of the signal transmitters includes at least one signal transmitter head, and each of the signal receivers includes at least one signal receiver head.

6. The detent wear detection device according to claim 5, characterized in that: The signal transmitter is embedded in the top surface of the chuck, and the signal receiver is arranged on the top of the process chamber; Alternatively, the signal transmitter is disposed on the top of the process chamber, and the signal receiver is embedded on the top surface of the chuck; Alternatively, the interior of the chuck is hollow, the signal transmitter is disposed in the chuck, and the signal receiver is disposed on the top of the process chamber; Alternatively, the interior of the chuck is hollow, the signal transmitter is disposed on the top of the process chamber, and the signal receiver is disposed in the chuck.

7. The detent wear detection device according to claim 2, characterized in that: The latch portion protrudes from the periphery of the driving mechanism and forms a clamping portion for clamping the wafer. The transmitting head of the signal transmitter and the receiving head of the signal receiver are arranged corresponding to the clamping portion.

8. The detent wear detection device according to any one of claims 2 to 7, characterized in that: Also includes a controller; The controller is connected to the signal receiver and the driving mechanism, and is used to calculate the wear value of the bayonet according to the detection data of the detection signal, and when it is detected that the bayonet located at the wafer clamping position reaches a preset wear value, control the corresponding driving mechanism to replace the bayonet located at the wafer clamping position; and / or, The controller is controlled to be connected to an alarm mechanism, and the alarm mechanism is used to generate an alarm signal.

9. The detent wear detection device according to any one of claims 1 to 7, characterized in that: The signal transmitter is a laser transmitter, and the signal receiver is a laser receiver; Alternatively, the signal transmitter is an infrared transmitter, and the signal receiver is an infrared receiver.

10. The detent wear detection device according to any one of claims 1 to 7, characterized in that: The connection line between the signal receiver and the signal transmitter is located on the side of the wafer clamped by the pin.

11. A semiconductor device, characterized in that: include: A chuck, a plurality of chuck pins spaced apart along the circumferential direction of the chuck, and a chuck pin wear detection device as claimed in any one of claims 1 to 9.

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