Ion beamlet capture device for ion implantation apparatus

Abstract

The application discloses an ion beam fragment capturing device of an ion implantation equipment, which comprises a beam line chamber, wherein the beam line chamber is arranged as an ion beam channel which is transversely penetrated; a front section of the bottom of the beam line chamber is arranged to be downwardly inclined in the direction of an ion beam outlet; a rear section is provided with a downwardly recessed accommodating cavity; a baffle is horizontally arranged above the accommodating cavity; and the baffle and the accommodating cavity form an ion beam fragment capturing space. The ion beam fragment capturing device can effectively capture ion beam fragments and greatly reduce the ion beam fragments flowing into a process cavity.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor technology, and in particular to an ion beam fragment capturing device of an ion implantation equipment. BACKGROUND

[0002] In the manufacture of semiconductor wafers, since the conductive performance of pure silicon is poor, a small amount of impurities is needed to change its structure and conductivity so as to become a useful semiconductor, which is called doping. At present, there are two methods of doping, i.e. high-temperature thermal diffusion method and ion implantation method, and the ion implantation method occupies a dominant position.

[0003] The ion implantation method is to inject the ions to be doped into materials in the form of an ion beam through acceleration and guidance of an ion implanter. The ion beam and atoms or molecules in the materials undergo a series of physical and chemical reactions. The incident ions gradually lose energy and cause the composition, structure and performance of the material surface to change. Finally, the ions are left in the material to optimize or change the performance of the material surface. The ion implantation has the advantages of precise control of energy and dose, good uniformity of doping, high purity, low-temperature doping, and no influence of injection materials, etc. At present, it has become a standard process for the manufacture of 0.25um feature size and large-diameter silicon wafers.

[0004] The ion implantation equipment, i.e. ion implanter, is mainly composed of five parts, i.e. ion source, magnetic analyzer, acceleration tube or deceleration tube, focusing and scanning system, and process cavity (target chamber and background processing system). When the equipment works, the ions introduced from the ion source pass through the magnetic analyzer to select the required ions. The analyzed ions are accelerated or decelerated to change the energy of the ions, and then pass through the two-dimensional deflection scanner to uniformly inject the ion beam into the material surface. The number of the implanted ions can be accurately measured by a charge integrator, and the energy of the implanted ions can be accurately controlled by adjusting the energy of the implanted ions.

[0005] In the ion implantation equipment, the ion beam formed by ionization of the ion source passes through the beam line chamber. The ion beam collides with the diaphragm to form by-products, i.e. ion beam fragments. The ion beam fragments flow into the process cavity together with the ion beam, which will bring adverse effects on the process of the wafer.

[0006] The invention patent CN108766909B discloses a device and method for improving the condensation phenomenon in low-temperature ion implantation, wherein the device comprises: a wafer transfer robot in an ion implanter, a heating module is arranged on the wafer transfer robot, and the heating module is used for heating a semiconductor substrate during the process of transferring the semiconductor substrate from a process chamber of the ion implanter to an external environment, a temperature detector arranged on the wafer transfer robot is used for detecting the temperature of the semiconductor substrate, and the heating module stops heating the semiconductor substrate when the temperature detector detects that the temperature of the semiconductor substrate reaches the temperature of the external environment; the wafer transfer robot comprises a robot arm and a robot gripper, the temperature detector is arranged at a connecting position of the robot arm and the robot gripper, and the heating module is arranged on both sides of the wafer transfer robot and faces the semiconductor substrate.

[0007] The invention directly heats the semiconductor substrate on the wafer transfer robot, avoids the condensation phenomenon, and reduces the probability of wafer sticking and fragmentation. However, the device structure is relatively complex, the modification cost is high, and it is difficult to avoid the generated fragments from entering the process chamber to cause wafer quality problems. SUMMARY

[0008] In order to solve the problem that the ion beam fragments flow into the process chamber together with the ion beam and cause adverse effects on the process of the wafer, the present application provides an ion beam fragment capturing device of an ion implantation equipment, which can effectively capture ion beam fragments and greatly reduce the ion beam fragments flowing into the process chamber. The technical scheme adopted by the present application is as follows:

[0009] An ion beam fragment capturing device of an ion implantation equipment, comprising a beamline chamber, the beamline chamber is arranged as an ion beam passage transversely penetrating; the front section of the bottom of the beamline chamber is arranged downwardly inclined along the direction of the ion beam outlet, and the rear section is provided with a downwardly recessed accommodating cavity, a baffle plate is arranged horizontally above the accommodating cavity, and the baffle plate and the accommodating cavity form an ion beam fragment capturing space.

[0010] Further, the baffle plate is provided with a plurality of narrow passages penetrating upward and downward.

[0011] Further, the narrow passages are arranged inclinedly.

[0012] Further, the narrow passages are arranged in two groups, and the inclination angles of the two groups are opposite.

[0013] Further, the two groups of narrow passages are arranged in a herringbone pattern.

[0014] Further, the width of the narrow passages is slightly larger than the diameter of the ion beam fragments.

[0015] Further, the front section of the beam line chamber bottom is inclined downward at an angle of 5-30 degrees in the direction of the ion beam outlet.

[0016] Further, the front section of the beam line chamber bottom is inclined downward at an angle of 15-20 degrees in the direction of the ion beam outlet.

[0017] Further, the cross-sectional shape of the accommodating cavity comprises a circle, an arc, and a polygon.

[0018] Further, the cross-sectional shape of the accommodating cavity is set as a trapezoid.

[0019] The present application has the following beneficial effects:

[0020] (1) The ion beam fragment capturing device of the present application can effectively capture ion beam fragments, greatly reducing the ion beam fragments flowing into the process cavity.

[0021] (2) In the present application, the front section of the beam line chamber bottom is inclined downward in the direction of the ion beam outlet, which can make the ion beam fragments falling to the bottom flow better into the accommodating cavity.

[0022] (3) The baffle provided above the accommodating cavity of the present application can prevent ion beam fragments from flying outward.

[0023] (4) The baffle of the present application is provided with a plurality of narrow passages penetrating up and down, which can make the ion beam fragments falling from above fall into the accommodating cavity, so as to avoid the ion beam fragments adsorbed or staying on the baffle from flowing to the process cavity after being combined with the ion beam.

[0024] (5) The narrow passages of the present application are inclined, which can avoid the ion beam fragments in the accommodating cavity from flying outward directly along the narrow passages. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a schematic diagram of the flow direction of ion beam fragments in the existing beam line chamber.

[0026] Figure 2 is a schematic diagram of the ion beam fragment capturing device of the embodiment of the present application.

[0027] Figure 3 is a schematic diagram of the flow direction of ion beam fragments in the beam line chamber of the embodiment of the present application.

[0028] Reference signs: 100-ion beam fragments, 200-decomposition aperture, 301-accommodating cavity, 302-baffle. DETAILED DESCRIPTION

[0029] In order to make the technical features, objectives and effects of the present application clearer, the specific embodiments of the present application are described. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application, i.e., the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0030] As shown in the prior ion implantation equipment, the ion beam formed by ionizing the ion source collides with the aperture 200 when passing through the beam line chamber, forming by-products, i.e., ion beam fragments 100, which flow into the process chamber together with the ion beam, causing adverse effects on the wafer in the process. Figure 1

[0031] Therefore, the present embodiment provides an ion beam fragment capturing device of an ion implantation equipment, which comprises a beam line chamber, the beam line chamber is provided as a transversely penetrating ion beam channel, and a resolving aperture 200 is arranged in the ion beam channel, as shown in Figure 2

[0032] As shown in Figure 2 , the front section of the bottom of the beam line chamber is inclined downward along the direction of the ion beam outlet, for displacing the ion beam fragments 100 falling to the bottom in the direction of the ion beam outlet. Specifically, the angle of the front section of the bottom of the beam line chamber inclined downward along the direction of the ion beam outlet can be set to 5-30 degrees. Preferably, the angle of the front section of the bottom of the beam line chamber inclined downward along the direction of the ion beam outlet is set to 15-20 degrees, which is the best.

[0033] As shown in Figure 2 and 3 , the rear section of the bottom of the beam line chamber is provided with a downwardly recessed accommodating cavity 301 for capturing the displaced ion beam fragments 100. A baffle plate 302 is horizontally arranged above the accommodating cavity 301 for preventing the ion beam fragments 100 from flying outward, so that the baffle plate 302 and the accommodating cavity 301 form an ion beam fragment 100 capturing space.

[0034] Specifically, the baffle plate 302 is provided with a plurality of up-and-down penetrating narrow channels, the width of the narrow channels is slightly larger than the diameter of the ion beam fragments 100, so that the ion beam fragments 100 falling from above fall into the accommodating cavity 301, to avoid the ion beam fragments 100 adsorbed or stayed on the baffle plate 302 flowing to the process chamber together with the ion beam.

[0035] In addition, the cross-sectional shape of the accommodating cavity 301 can be circular, arc-shaped or polygonal.

[0036] ​​In a preferred embodiment of the present application, the narrow passages are arranged in a slanting manner to avoid the ion beam fragments 100 in the accommodating cavity 301 from flying out directly along the narrow passages. The narrow passages can be arranged in two groups, and the two groups are arranged in opposite slanting angles.

[0037] In another preferred embodiment of the present application, the two groups of narrow passages are arranged in a herringbone pattern to better limit the ion beam fragments 100 in the accommodating cavity 301 from flying out.

[0038] In still another preferred embodiment of the present application, the cross-sectional shape of the accommodating cavity 301 is preferably arranged in a trapezoidal shape.

[0039] Therefore, the ion beam fragment capturing device provided by the present application can effectively capture ion beam fragments and greatly reduce the ion beam fragments flowing into the process cavity.

[0040] It should be noted that the terms "center", "upper", "lower", "left", "right", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the present application is used, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

Claims

1. An ion beamlet trapping device of an ion implantation apparatus, characterized by, The beam line chamber is provided with an ion beam channel transversely penetrating therethrough; a front section of the bottom of the beam line chamber is provided in a downwardly inclined manner along the direction of the ion beam outlet, and the angle of inclination is 5-30 degrees; a rear section is provided with a downwardly recessed accommodating cavity; a baffle is horizontally arranged above the accommodating cavity, and the baffle and the accommodating cavity form an ion beam fragment capturing space. The baffle is provided with a plurality of narrow channels penetrating therethrough in an up-down direction, and the narrow channels are provided in an inclined manner; the narrow channels are provided in two groups, and the angles of inclination of the two groups are opposite; the two groups of narrow channels are provided in a herringbone shape; the width of the narrow channels is slightly greater than the diameter of the ion beam fragments, so that the ion beam fragments falling from above fall into the accommodating cavity.

2. The ion beamlet fragment capture apparatus of an ion implantation apparatus according to claim 1, wherein, The angle of inclination of the front section of the bottom of the beam line chamber along the direction of the ion beam outlet is 15-20 degrees.

3. The ion beamlet fragment capturing apparatus of an ion implantation apparatus according to claim 1, wherein, The cross-sectional shape of the accommodating cavity is provided in a circular shape, an arc shape or a polygonal shape.

4. The ion beamlet skimmer of an ion implantation apparatus of claim 1, wherein, The cross-sectional shape of the accommodating cavity is provided in a trapezoidal shape.

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