KR100568112B1 - System and method for controlling scan interlock of high-energy ion implanter - Google Patents

Abstract

The present invention relates to a scan interlock system of a high energy ion implantation facility and a control method thereof. The scanning assembly includes a sensor unit for detecting a movement due to scan moving of the position transducer. The system controller monitors the moving distance according to scan moving from the processor, and when an abnormality occurs, interlocks the ion implantation facility. Therefore, in the scan moving operation, when the scan operation does not move to the end and returns from the middle due to a defect such as an SST (Scan Spin Tilt) interface unit, a power supply IC, or a position transducer, By controlling the interlock of, process defects are prevented.

Ion Implantation, Scanning Device, Scan Moving, Interlock, Sensor

Description

Scan interlock system of high energy ion implantation system and its method {SYSTEM AND METHOD FOR CONTROLLING SCAN INTERLOCK OF HIGH-ENERGY ION IMPLANTER}

1 is a block diagram showing a schematic configuration of a typical high energy ion implantation facility;

2 is a block diagram showing the configuration of a system for controlling the scan interlock of an ion implantation facility according to the present invention;

3 is a block diagram showing the configuration of the system control unit shown in FIG. 2;

4 is a cross-sectional view showing a detailed configuration of the scanning assembly shown in FIG. And

5 is a flowchart illustrating a procedure for controlling interlock according to a scan moving operation according to the present invention.

Explanation of symbols on the main parts of the drawings

100: scan interlock system 102: disk assembly

104: wafer 106: spindle assembly

110: scanning assembly 112: position transducer

114: scan shaft 116: tilt shaft

118: lead screw 120: rail

121: sensor bar 122, 128: reset switch

124, 126: sensor 130: system control unit

132: main controller 134: PDC controller

140: power supply IC

The present invention relates to an ion implantation facility, and more particularly, to a system for controlling a scan interlock of an ion implantation facility and a control method thereof.

In general, the ion implantation facility 10 for an ion implantation process is, for example, a high energy ion implantation facility (model name: Genus 1510/1520) of Varian Semiconductor Equipment Associates, Inc. of the United States, schematically shown in FIG. As shown, it comprises a source unit 2, an injector unit 4, an accelerator unit 6 and a process chamber unit 8.

Although not shown in FIG. 1, the source unit 2 has an arc chamber that ionizes a gas to generate an ion beam. The injector unit 4 is a charge exchange cell that receives ionized cations from the arc chamber and converts them into ions with the properties of negative ions, and chambers at 90 degrees angles to the ions of the various gases produced from the source. By using the mass difference of the gas through the magnetic field, the analysis magnet (analyzer magnet) extracting only the ions of the desired gas and the anion analyzed from the analysis magnet are applied to about 90 KeV power to accelerate the ion beam with higher energy. It includes a pre accelator.

The accelerator unit 6 includes an injector faraday cup, a low gnergy lens, a tandetron ass'y, a high energy lens and a beam. And a filter magnet (beam filter magnet).

The injector Faraday cup senses the number of ions from the ion beam output from the pre accelerator. As the ions generated at the source pass through the charge exchange cell, the analysis magnet and the pre-accelerator, the beam size increases. Low-energy lenses use this increased beam size to minimize the beam size by using electrical properties.

The TANDRON assembly consists of one Hv stack and two accelerators, with approximately 750 KeV of power output from the Hv stack provided by the two accelerators. Taendeo center of the torch assembly, the nitrogen stripper (N ₂ stripper) is located, the nitrogen stripper serves to convert the anionic ion by charge EXCHANGE cells using nitrogen as the original nature of the cation. Thus, the Tandertron assembly uses a charge exchange cell to double the effect of a single power supply. The beam focused primarily by the low energy lens increases the size of the beam again through the Tandertron assembly.

The high-energy lens minimizes the beam size by using electrical properties of the increased beam size. And the beam converted from anion to cation by the nitrogen stripper in the tandertron assembly is divided into several forms. The beam filter magnet selectively filters various types of cations and only the desired type of ions.

Beam Faraday cups convert negative ions to positive ions by nitrogen strippers in the Tandertron assembly and sense the amount of converted ions in the Beam Faraday cup. The amount of beam detected also determines the dose calculation, the number of scans and the ion implantation time.

The process chamber unit 8 is connected to a process chamber including a process chamber including a disk into which a wafer is loaded for ion implantation, a disk Faraday cup for sensing the amount of ion implantation, and a process chamber to uniformly implant the wafer. And a scanner 12 loaded in to perform scan, spin and tilt operations.

The scanner 12 is mechanically connected to the disk assembly into which the wafer of the process chamber is loaded, and performs a scan moving operation to uniformly implant ions in the X-axis direction of the wafer.

However, in the scan moving operation, a phenomenon in which the scan operation does not move to the end and returns from the middle due to a defect such as an SST (Scan Spin Tilt) interface unit, a power supply IC, or a position transducer occurs. Due to this phenomenon, the ion implantation process is not uniformly ion implanted on the entire surface of the wafer, resulting in process defects.

As a result, productivity decreases by increasing the processing time for facility failure measures. In addition, after the ion implantation process is completed, the cause generated during scan moving is not transmitted to the engineer of the subsequent process, which causes a larger process accident.

An object of the present invention is to solve the above problems, to provide a scan interlock system for detecting in advance the occurrence of abnormalities during the scan moving operation, and to prevent the process accident.

In addition, another object of the present invention is to solve the above problems, to provide a control method of the interlock system for controlling the operation of the ion implantation facility, if an abnormality occurs by monitoring the scan moving operation of the ion implantation facility.

According to one aspect of the present invention for achieving the above object, a scan interlock system of a high-energy ion implantation facility, the scanner includes a linear reciprocating motion to uniformly implant the ion in the X-axis direction of the loaded wafer; A sensor unit for detecting a movement of the scanner according to the linear reciprocating motion of the scanner; And a control unit for monitoring a movement distance according to the movement of the scanner from the sensor unit and stopping the operation of the scanner when an abnormality occurs in the movement distance.

In a preferred embodiment of this aspect, the scanner comprises; The sensor unit has a sensor bar detectable at one side, and a position transducer for linear reciprocating motion between the starting point and the last point for ion implantation of the wafer, and receiving the driving power of the position transducer from the power supply unit. A scan motor for driving the transducer and a lead screw for linear movement of the position transducer. The control unit; A power supply for supplying the drive power of the position converter, and, if the abnormality occurs, a controller for disconnecting the drive power of the position converter from the power supply. And the sensor unit; And a reset switch provided to reset the controller in response to the first sensor, the second sensor provided at the last point, and the first and second sensors.

According to another aspect of the present invention for achieving the above object, a position transducer and a sensor unit for detecting a linear reciprocating motion of the position transducer and a power supply for supplying the driving power of the position transducer, A control method of a scan interlock system for controlling a scan moving operation includes: loading a wafer; Controlling scan moving of the position transducer for uniform ion implantation into a wafer; Monitoring the scan moving of the position transducer from the sensor unit during the scan moving operation to determine whether an error occurs in the movement of the position transducer; If an error occurs, stopping the scan moving operation by controlling the power supply to cut off the driving power of the position converter.

In a preferred embodiment of this feature, the determining step comprises; The sensor may sequentially receive data detected by the first and second sensors according to the movement of the position transducer, and recognize that an error occurs when the scan moving operation is performed when the data are the same data.

Therefore, according to the present invention, a phenomenon in which the scan operation does not move to the end without returning to the end due to a defect such as an SST (Scan Spin Tilt) interface unit, a power supply IC, or a position transducer during scan moving operation may occur. When generated, process failure is prevented by controlling the interlock of the ion implantation facility.

DETAILED DESCRIPTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing the configuration of a system for controlling interlock during scan moving operation of an ion implantation facility according to the present invention.

Referring to the drawings, the scan interlock system 100 may include a scanning assembly 110 connected to a disk assembly 102 provided in a process chamber and a system controller 130 for controlling overall operations of the scanning assembly 110. Include.

As shown in FIG. 3, the system controller 130 includes a power supply IC 140 that supplies driving power of the scanning assembly 110 and a PDC controller that senses an amount of ions for ion implantation supplied to the process chamber. 134 and a main controller 132 that receives the sensing information according to the scan moving from the scanning assembly 110 and controls the interlock of the ion implantation facility.

The PDC controller 134 measures the amount of ions supplied to the process chamber unit and outputs the amount of ions to the main controller 132.

The main controller 132 receives the ion amount information output from the PDC controller 134 and controls the scan, spin, and tilt operations to uniformly supply ion implantation to the wafer. In particular, according to the present invention, the main controller 132 monitors the scan moving operation by the sensors (121 to 128 of FIG. 4) provided in the scanning assembly 110, if an error occurs, Control the lock.

The power supply IC 140 is provided in, for example, a scan spin tilt (SST) interface board, and supplies driving power (for example, about 10 V) of the position converter 112.

The scanning assembly 110 is provided at an end station of an ion implantation facility, for example, and as shown in FIG. 4, ion implantation in the X axis direction of the wafer 104 loaded in the disk assembly 102. Position transducer 112 for linear reciprocating motion, scan motor for rotating motion, and lead screw 118 for converting rotational motion of the scan motor into linear reciprocating motion for linear reciprocating motion. It includes.

Specifically, the scanning assembly 110 includes sensors 124 and 126 at inboard and outboard positions, respectively, to detect linear reciprocation of the position transducer 112. In addition, the scanning assembly 110 includes reset switches 122 and 128 for initializing the main controller 132 in response to the sensors 124 and 126. And at one end of the position transducer 112, the sensors 124, 126 is provided with a sensor bar 121 to detect the movement of the position transducer 112.

At this time, the load position indicates a position for loading and unloading the wafer 104, and the inboard position is a starting position for implanting ions, that is, the beginning of the wafer, and the outboard position is for implanting ions. For the last position, ie the end of the wafer.

Therefore, the scanning assembly 110 moves in the lateral direction to inject ions in the X-axis direction of the wafer, processes the scan operation, and performs rotational movement to inject ions in the Y-axis direction of the wafer. The tilt operation is then operated to load and unload the wafer at the loading position of the wafer and to implant ions at the tilted position of about 7 degrees.

As shown in FIG. 4, the sensors 121 to 128 are provided in the inboard position and the first reset 122 and the first sensor 124 for the reset operation and the position sensing operation, respectively. 128 and the second sensor 126 are provided in the outboard position. Then, by detecting the movement of the sensor bar 121 provided in the position transducer 112, the movement distance of the linear reciprocating motion of the position transducer 112 is sensed.

At this time, during the scan moving operation, a phenomenon in which the scan operation does not move to the end between the inboard and the outboard due to a malfunction of the motor or the power supply IC 140, etc., may be returned. For example, power supply IC 140 supplies about 10V of power to position converter 112. However, if a power supply voltage of exactly 10 V is not supplied from the power supply IC 140 to the position converter 112, an abnormality occurs in the moving distance according to the scan moving of the position converter 112. With a 10 V supply voltage, the position transducer 112 has a scan moving distance of about 10 inches, but when a 7 V supply voltage is supplied, about 9 inches is moved.

Specifically, the operation of the sensors 121 to 128 is as follows.

First, the sensors 124 and 126 sense low logic level '0' when the first sensor 124 is operated, and high logic level '1' when the second sensor 126 is operated. .

When the normal scan moving operation moves from the inboard position to the outboard position, the scan operation moves to the inboard position simultaneously with the spin up. At this time, the main controller 132 is initialized by operating the first reset switch 122. Subsequently, when passing through the first sensor 124, the main controller 132 senses '0' and when passing through the second sensor 126, the main controller 132 senses '1'. Therefore, the main controller 132 sequentially detects '0' and '1' according to the normal scan moving when moving from the inboard position to the outboard.

In addition, when moving from the outboard to the inboard position, when the scan operation is located at the outboard position, the second reset switch 128 operates to initialize the main controller 132. Subsequently, when passing through the second sensor 126, the main controller 132 senses '1' and when passing through the first sensor 124, senses '0'. Therefore, the main controller 132 sequentially detects '1' and '0' according to the normal scan moving when moving from the outboard position to the inboard position.

However, the abnormal scan moving operation, for example, when moving from the inboard position to the outboard position and returns in the middle without moving to the outboard position, simultaneously moves to the inboard position and operates the first reset switch 122 to operate the main controller 132. ) And when passing through the first sensor 124, the main controller 132 detects '0'. It does not go to the outboard position then it cannot pass through the second sensor 126. Since the rescan operation passes through the first sensor 124, the main controller 132 detects '0'. Accordingly, the main controller 132 sequentially detects '0' and '0'.

In addition, when moving from the outboard position to the inboard position, when returning from the middle without going from the outboard position to the inboard position, the main controller 132 by operating the second reset switch 128 at the same time as moving to the outboard position. When the initializing and passing through the second sensor 126, the main controller 132 detects '1'. Subsequently, it does not go to the inboard position and thus cannot pass the first sensor 124. Since the rescan operation passes through the second sensor 126, the main controller 132 detects '1'. Therefore, the main controller 132 sequentially detects '1' and '1'. Table 1 below shows normal and malfunction states of the detection result according to the scan operation.

Scan action First switch 2nd switch result Inboard-> Outboard 0 0 Malfunction Inboard-> Outboard 0 One normal Outboard-> Inboard One 0 normal Outboard-> Inboard One One Malfunction

Therefore, according to the present invention, if a malfunction occurs by detecting a moving distance during scan moving of the ion implantation facility, the operation of the position converter 112 is emphasized to control the interlock of the ion implantation facility.

5 is a flowchart illustrating a procedure for controlling an interlock by monitoring a scan moving operation according to the present invention. This procedure is a program processed by the main controller 132, which is stored in an internal memory (not shown) of the main controller 132.

Referring to the drawing, when the wafer 104 is loaded in the disk assembly 102 in step S150, the scan moving operation is controlled in step S152.

In step S154, it is determined whether a motion malfunction occurs by the position detected from the at least one sensors 121 to 128. At this time, as shown in Table 1, the malfunction of the position transducer 112 is determined using the data sensed by the first and second sensors 124, 126.

As a result of the determination, if a malfunction of the position converter 112 occurs, this procedure proceeds to step S156 to control the driving power to be cut off by the power supply IC 140 and generates an interlock to stop the ion implantation facility in step S158. Let's do it.

If no malfunction occurs in step S154, the procedure goes to step S152 to control the scan moving operation corresponding to the ion implantation process.

As described above, the scan interlock system 100 of the present invention is equipped with sensors at the sections where the scanner moves, that is, the inboard and the outboard positions, so that the scan movement distance is always monitored, thereby causing scan malfunction of the high energy ion implantation facility. If a malfunction occurs, the interlock is controlled by focusing on the ion implantation facility.

As described above, the scan interlock system of the ion implantation apparatus of the present invention includes sensors in the scanning assembly that detect the scan moving operation of the position transducer, thereby monitoring the scan moving operation, and if an abnormality occurs during the scan moving operation, Interlock control of the ion implantation facility. Therefore, process defects due to scan moving errors can be prevented.                     

In addition, by minimizing process defects due to scan moving, productivity is increased through uniform ion implantation during the ion implantation process.

In addition, productivity is improved by quickly identifying and correcting the error cause of the scan moving operation in advance through the sensors of the scanning assembly.

Claims (6)

In a scan interlock system in a high energy ion implantation facility: A scanner for linear reciprocating motion to uniformize ion implantation in the X axis direction of the loaded wafer; A sensor unit for detecting a movement of the scanner according to the linear reciprocating motion of the scanner; And a control unit for monitoring a movement distance according to the movement of the scanner from the sensor unit and stopping the operation of the scanner when an abnormality occurs in the movement distance. The method of claim 1, The scanner; A position transducer having a sensor bar detectable at one side of the sensor, and a linear reciprocating motion between a start point and a last point for ion implantation of the wafer; A scan motor which receives the driving power of the position converter from the power supply and drives the position converter; And a lead screw for linear movement of said position transducer. The method of claim 1, The control unit; A power supply unit for supplying driving power of the position converter; And a controller for disconnecting driving power of the position converter from the power supply unit when the abnormality occurs. The method of claim 1, The sensor unit; A first sensor provided at the starting point; A second sensor provided at the last point, And a reset switch respectively provided to reset the controller in response to the first and second sensors. A control method of a scan interlock system for controlling a scan moving operation of the position transducer, comprising a position transducer, a sensor unit for detecting linear reciprocation of the position transducer, and a power supply unit for supplying driving power of the position transducer. : The wafer is loaded; Controlling scan moving of the position transducer for uniform ion implantation into a wafer; Monitoring the scan moving of the position transducer from the sensor unit during the scan moving operation to determine whether an error occurs in the movement of the position transducer; And if an error occurs, stopping the scan moving operation by controlling the power supply to cut off the driving power of the position converter. The method of claim 5, wherein The determining step includes; In response to the movement of the position converter, data received from the first and second sensors respectively positioned at the start point and the end point for ion implantation of the wafer are sequentially received. If the data are the same data, the scan moving operation is performed. Control method, characterized in that the recognition of the error has occurred.

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