A device for measuring horizontal and vertical angles of ion beams

Abstract

The invention discloses a device for measuring the horizontal and vertical angles of an ion beam, comprising a vacuum chamber in which an ion beam is transmitted; a horizontal and vertical angle Faraday measuring cup for measuring the inclination angle of the ion beam relative to the normal of the incident surface of the Faraday cup in the horizontal plane and the vertical plane; a horizontal angle measuring driving motor directly drives a four-bar linkage through a coupling, each cup is connected to the terminal of the connecting rod, and drives the rotation of each cup; a vertical angle measuring driving motor drives a cup mounting seat equipped with multiple Faraday cups to rotate through a synchronous belt transmission mechanism, and all cups perform a revolution motion. The invention can be used for measuring the beam injection angle at the terminal of the target chamber of an ion implanter, and the position of the target stage can be adjusted through these angle parameters, thereby improving the ion implantation accuracy of silicon wafers, including the implantation angle and uniformity.

Description

Technical Field

[0001] The invention relates to semiconductor device manufacturing equipment, in particular to an ion beam horizontal and vertical angle measuring device. Background Art

[0002] Semiconductor device manufacturing technology and processes are very complex, and ion implantation doping is a very critical process in the semiconductor device manufacturing process. Compared with conventional thermal doping processes, ion implantation doping processes have the advantages of high-precision dose uniformity and repeatability, small lateral diffusion, etc., which overcomes the limitations of conventional processes, improves the integration, speed, yield and life of circuits, and reduces costs and power consumption. With the continuous improvement of semiconductor process technology, higher requirements are put forward for ion implantation doping, mainly including the control of implantation depth and implantation uniformity. In order to improve the accuracy of ion implantation depth and the uniformity of ion implantation silicon wafers, the above requirements can be achieved in two ways. One method is to improve the beam state of the ion implanter, and the other method is to improve the measurement accuracy of the beam state and adjust the position of the silicon wafer to improve the implantation accuracy. When a model of ion implanter reaches mass production and use, it proves that there is not much room for improvement in the optical transmission system. At this time, it is necessary to improve the measurement accuracy of the beam reaching the target chamber.

[0003] The general beam angle measurement device can only measure the horizontal deflection angle. The horizontal angle is also measured by the cooperation of a mobile Faraday and a fixed Faraday. This measurement mechanism is relatively complicated, but a large number of experiments have shown that the vertical angle of the beam has the greatest impact on the injection depth. This requires the design of a new angle measurement device to measure the horizontal and vertical angles at the same time. The new device can complete the measurement of horizontal and vertical angles at the same time through an integral component. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a multifunctional and multi-position beam angle measurement device to address the deficiencies of the prior art. The device can simultaneously measure the horizontal angle and vertical angle of the beam and can simultaneously measure the vertical deflection angles of multiple positions. The horizontal angle can be measured without the need for coordination with a mobile Faraday at the front end.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: an ion beam horizontal and vertical angle measuring device, mainly comprising: an ion beam horizontal and vertical angle measuring device, characterized in that it includes: a vacuum chamber assembly, in which the ion beam is transmitted and provides support for the measuring mechanism; a horizontal and vertical angle Faraday measuring cup assembly, used to measure the inclination angle of the ion beam relative to the normal of the incident surface of the Faraday cup body in the horizontal plane and the vertical plane; a vertical angle measurement drive mechanism, used to drive all Faraday measuring cup assemblies to rotate relative to the chamber; a horizontal angle measurement drive mechanism, used to drive the rotation of each Faraday measuring cup assembly relative to the Faraday measuring assembly bracket; a beam-limiting light barrier is provided at the entrance of the ion beam, and only a part of the regular-shaped beam can pass through.

[0006] The two sides of the Faraday cup are composed of two identical graphite parts, and a graphite column is installed in the middle of the cup; there are rectangular grooves with equal spacing on the graphite column, and the rectangular grooves used for vertical angle measurement are transverse grooves with a depth of 1 / 2 of the thickness of the column, and the rectangular grooves used for horizontal angle measurement are longitudinal grooves with a depth of 1 / 2 of the thickness of the column; the graphite column is supported by a ceramic insulating part to insulate it from the surrounding auxiliary parts, and the upper and lower insulating parts are connected to the bracket through two angular contact shaft ball bearings, so that each cup can rotate relative to the bracket; suppression magnets are installed on both sides of each cup, and there are suppression magnets at the inlet and outlet of the cup. When the cup rotates, the magnet assembly rotates with the cup; The circumferential position of the Faraday cup can be adjusted by rotating the Faraday cup assembly. When the Faraday cup is used for horizontal angle measurement, the cup with a longitudinal groove on one side faces the beam incident direction. When the Faraday cup is used for vertical angle measurement, the cup with a transverse groove on one side faces the beam incident direction. When measuring the horizontal angle, the horizontal angle measurement drive mechanism drives each Faraday cup to rotate around the vertical center line of the cup. When measuring the vertical angle, the vertical angle measurement drive mechanism drives the Faraday cup assembly to rotate relative to the horizontal center plane. The angle measurements in both directions use the position corresponding to the minimum beam value of the Faraday cup data collected as the actual deflection angle of the beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 Axonometric view of the overall layout of the beam angle measurement device;

[0008] Figure 2 A top view of the overall layout of the beam angle measurement device;

[0009] Figure 3 Schematic diagram of the horizontal angle measurement surface of the Faraday measuring cup assembly;

[0010] Figure 4 Schematic diagram of the vertical angle measurement surface of the Faraday measuring cup assembly;

[0011] Figure 5 A cross-sectional view of the center plane position of a single Faraday measuring cup assembly; DETAILED DESCRIPTION

[0012] like Figure 1 and Figure 2 As shown, the present invention includes a vacuum chamber assembly 130, in which the ion beam is transmitted and provides support for the measuring mechanism; a horizontal and vertical angle Faraday measuring cup assembly 110, which is used to measure the inclination angle of the ion beam relative to the normal of the incident surface of the Faraday cup body in the horizontal plane and the vertical plane; a vertical angle measurement drive mechanism 120, which is used to drive all Faraday measuring cup assemblies to rotate relative to the chamber; a horizontal angle measurement drive mechanism 100, which is used to drive the rotation of each Faraday measuring cup assembly relative to the Faraday measuring assembly bracket; a beam limiting light barrier 12 is provided at the entrance of the ion beam, and only a part of the regular shape beam can pass through. The function of this component is to improve the measurement accuracy and reduce the influence of the excess beam on the measurement accuracy.

[0013] The vacuum chamber assembly 130 is connected to the beam transmission chamber 150, 140 is the beam transmission direction, the interior of the vacuum chamber assembly 130 is a high vacuum environment, and the exterior is an atmospheric environment, so the horizontal and vertical angle Faraday measurement cup assembly 110 installed on the chamber needs to be isolated from the atmosphere, so as to ensure the high vacuum inside the vacuum chamber assembly 130. The vertical angle measurement drive mechanism 120 and the horizontal angle measurement drive mechanism 100 motor and other components are installed outside the chamber, and the horizontal angle measurement drive mechanism 100 motor drive is connected to the rotating magnetic fluid seal 4 through the welding bellows 3, and the welding bellows 3 can provide six degrees of freedom, so as to ensure that the connecting rod mechanism is moving while the chamber assembly 130 is still in a high vacuum. The magnetic fluid seal 4 provides vacuum sealing for the vacuum chamber assembly 130 and the horizontal angle measurement drive mechanism 100. The vacuum chamber assembly 130 and the horizontal angle measurement drive mechanism 100 can also rotate relative to each other, so that when the measurement surface is switched, the horizontal angle measurement drive mechanism 100 can rotate with the horizontal and vertical angle Faraday measurement cup assembly 110. The vertical angle measurement drive mechanism 120 is connected to the vertical angle Faraday measurement cup assembly 110 through the component 10, and the component 11 provides a buffer connection between the vertical angle measurement drive mechanism 120 and the vacuum chamber assembly 130. The component 11 can be a magnetic fluid seal or can be sealed by a sealing ring, so that the vertical angle measurement drive mechanism 120 drives the horizontal and vertical angle Faraday measurement cup assembly 110 to rotate as a whole.

[0014] The horizontal angle measurement drive mechanism 100 drives the coupling through the motor 1, and the coupling drives the crank 2 to rotate. One end of the crank 2 is hinged to the frame through a bearing, and the other end is hinged to the connecting rod 7 through a bearing. There are also multiple hinged positions for installing bearings on the connecting rod 7, which are hinged to the crank 5. The other end of the crank 5 is firmly connected to the central supporting ceramic part S02 of each Faraday measuring cup assembly 160 through a key or pin. There is no relative movement between the crank 5 and the ceramic part S02. In this way, several Faraday measuring cup assemblies 160 can be driven to rotate around the center at the same time by one motor.

[0015] The principle of the vertical angle measurement drive mechanism 120 is to drive the synchronous pulley through the motor 8, and the synchronous pulley drives all the Faraday measuring cup assembly support shafts 10 to perform rotational motion. The rotation method is that all the Faraday measuring cup assemblies rotate around the horizontal fixed axis. The vacuum seal at this position can be achieved by magnetic fluid seal or sealing ring seal. The other end of the Faraday measuring cup assembly is connected to the flange of the horizontal angle measurement drive mechanism 100, and a magnetic fluid sealing assembly is arranged between the flange and the vacuum chamber assembly. In this way, it can be ensured that each measuring cup has two rotational motions. The overall rotation of the Faraday measuring cup assembly is revolution, and the rotation of each Faraday measuring cup assembly around the axis is rotation.

[0016] The horizontal and vertical angle Faraday measuring cup assembly 110 is composed of a plurality of Faraday measuring cup assemblies 160, each of which is hinged to an external mounting support frame via two angular contact ball bearings S01. Figure 5 As shown, this forms the rotational freedom of each Faraday measuring cup assembly 160. The external mounting support frame is composed of a side plate A01, two transverse plates A02, and a side plate A03, wherein one transverse plate A02 has a mounting hole corresponding to the center position of each Faraday measuring cup assembly 160, and a bearing is installed in the center of the hole to provide support for the crank 5.

[0017] The two sides of the Faraday measuring cup assembly 160 are composed of two identical graphite parts S03. A graphite column S05 is installed in the middle of the cup. The graphite column S05 has rectangular grooves with equal spacing, which are used for vertical angle measurement. The rectangular grooves are transverse grooves, such as Figure 4 As shown, the depth is 1 / 2 of the thickness of the graphite column S05, and the surface 300 is the beam incident measurement surface; the rectangular groove used for the horizontal angle measurement surface is a longitudinal groove, such as Figure 3As shown, the depth is 1 / 2 of the thickness of the graphite column S05, and the surface 200 is the beam incident measurement surface; the graphite column S05 is supported by a ceramic insulating member S02 to insulate it from the surrounding auxiliary components, and the upper and lower insulating members are connected to the bracket through two angular contact bearings S01, so that each cup body can rotate relative to the bracket; suppression magnets S04 are installed on both sides of each cup body, and there are suppression magnets S04 at the inlet and outlet of the cup body. When the cup body rotates, the magnet assembly rotates with the cup body; the circumferential position of the Faraday cup body can be adjusted by rotating the Faraday cup body assembly. When the Faraday cup body is used for horizontal angle measurement, as shown in FIG. Figure 3 As shown, the cup body with a longitudinal groove faces the incident direction of the beam, and the surface 200 faces the incident direction of the beam; when the Faraday cup body is used for vertical angle measurement, as shown in FIG. Figure 4 As shown, the cup body with a side having a transverse groove faces the incident direction of the beam, and the surface 300 faces the incident direction of the beam.

Claims

1. An ion beam horizontal and vertical angle measuring device, characterized in that: include: A vacuum chamber assembly, in which the ion beam is transmitted and provides support for the measuring mechanism; a horizontal and vertical angle Faraday measuring cup assembly, used to measure the inclination angle of the ion beam relative to the normal of the incident surface of the Faraday cup body in the horizontal and vertical planes; a vertical angle measurement drive mechanism, used to drive all Faraday measuring cup assemblies to rotate relative to the chamber; a horizontal angle measurement drive mechanism, used to drive the rotation of each Faraday measuring cup assembly relative to the Faraday measuring assembly bracket; a beam-limiting light barrier is provided at the entrance of the ion beam, and only a part of the regular-shaped beam can pass through; the two sides of the cup body of the Faraday measuring cup assembly are composed of two identical graphite parts, and a graphite column is installed in the middle of the cup body; there are rectangular grooves with equal spacing on the graphite column, which are used for vertical angle measurement. The rectangular grooves are horizontal The groove has a depth of 1 / 2 of the thickness of the column and is used for horizontal angle measurement. The rectangular groove is a longitudinal groove with a depth of 1 / 2 of the thickness of the column. The graphite column is supported by a ceramic insulating member to insulate it from the surrounding auxiliary components. The upper and lower insulating members are connected to the bracket through two angular contact bearings, and each cup body rotates relative to the bracket. Suppression magnets are installed on both sides of each cup body, and there are suppression magnets at the inlet and outlet of the cup body. When the cup body rotates, the magnet assembly rotates with the cup body; the circumferential position of the Faraday cup body is adjusted by rotating the Faraday cup body as a whole assembly. When the Faraday cup body is used for horizontal angle measurement, the cup body with the longitudinal groove on one side faces the incident direction of the beam. When the Faraday cup body is used for vertical angle measurement, the cup body with the transverse groove on one side faces the incident direction of the beam.

2. The ion beam horizontal and vertical angle measuring device according to claim 1, characterized in that: The horizontal angle measurement drive mechanism is driven by a parallelogram linkage mechanism. Each measuring cup is provided with a crank, and the cranks on all cups are connected to the crank driven by the motor through a connecting rod. When measuring the horizontal angle, the rotational motion of multiple Faraday measuring cups is consistent. The rotation is the rotation of the Faraday cup relative to its own vertical axis. The motor and the crank on the motor are installed in the atmosphere, and the connecting rod is in a vacuum. The crank on the motor and the connecting rod are connected by a flexible welded bellows.

3. The ion beam horizontal and vertical angle measuring device according to claim 1, characterized in that: The vertical angle measurement drive mechanism drives the synchronous pulley through the motor, and the synchronous pulley drives the support shaft of all Faraday measuring cup assemblies to rotate. The rotation method is that all Faraday measuring cup assemblies rotate around the horizontal fixed axis. The vacuum seal is achieved by magnetic fluid seal or sealing ring seal. One end of the Faraday measuring cup assembly is connected to the flange of the horizontal angle measurement drive mechanism. A magnetic fluid sealing assembly is arranged between the flange and the vacuum chamber assembly, which can ensure that each measuring cup has two rotational movements. The overall rotation of the Faraday measuring cup assembly is revolution, and the rotation of each Faraday measuring cup assembly around the axis is rotation.

4. The ion beam horizontal and vertical angle measuring device according to claim 1, characterized in that: The beam limiting light barrier is provided with a slender strip hole, and the middle position of each measuring cup body corresponds to a beam limiting light barrier hole.

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