An electron generator and ion implantation apparatus

Abstract

An electron generator and ion implantation equipment, the electron generator comprises a reaction chamber, the reaction chamber is connected with a gas source and a radio frequency power source, and is used for generating a radio frequency electric field under the action of the radio frequency power source, and dissociating gas from the gas source through the radio frequency electric field to generate electrons; an outlet piece is arranged on the reaction chamber, and an electron outlet connected with the inside of the reaction chamber is arranged in the middle of the outlet piece, and the electrons in the inside of the reaction chamber overflow through the electron outlet, and the material of the outlet piece is a non-metallic conductor. The electron generator adopts the outlet piece made of the non-metallic conductor material, and can avoid metal pollution of the ion beam.

Description

Technical Field

[0001] This utility model relates generally to the field of semiconductor technology, and more specifically to an electron generator and ion implantation device. Background Technology

[0002] In semiconductor manufacturing, ion implantation equipment is used to accelerate and implant ions into semiconductor materials, thereby controlling the semiconductor's conductivity. Ion beam bombardment of a wafer causes a large amount of positive charge to accumulate on the wafer surface. To prevent this positive charge from charging the wafer, an electron generator is used to generate electrons to neutralize the ion beam. On one hand, the electrons generated by the electron generator ensure the electrical neutrality of the wafer surface; on the other hand, because ions and electrons have different electrical charges, the electrons can prevent ion divergence, thus contributing to the uniformity of the ion beam.

[0003] In the manufacturing process, it is necessary to strictly control and monitor the metal content and uniformity of the ion beam. If there are problems with the metal content or ion beam uniformity, it will affect the product yield. As one of the key components closest to the wafer in the ion implantation equipment, problems with the electron generator in these two aspects will directly affect the product yield and may even lead to scrapping. Utility Model Content

[0004] The utility model description section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This utility model description section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] One embodiment of this utility model provides an electron generator, the electron generator comprising:

[0006] A reaction chamber is connected to a gas source and a radio frequency power supply. It is used to generate a radio frequency electric field under the action of the radio frequency power supply, and to dissociate the gas from the gas source through the radio frequency electric field to generate electrons.

[0007] An outlet component is disposed on the reaction chamber. An electron outlet connected to the interior of the reaction chamber is disposed in the middle of the outlet component. Electrons inside the reaction chamber overflow through the electron outlet. The outlet component is made of a non-metallic conductor.

[0008] In one embodiment, the material of the export component includes graphite.

[0009] In one embodiment, the outlet component is fixed to the reaction chamber by screws, the screws being made of a non-metallic conductor.

[0010] In one embodiment, the screw is made of graphite.

[0011] In one embodiment, the electron generator includes at least three outlet elements arranged at intervals, the electron outlets being orifice-shaped.

[0012] In one embodiment, the at least three outlet pieces are of the same size and are arranged at equal intervals.

[0013] In one embodiment, the width of the electronic outlet ranges from 0.3 mm to 1.5 mm.

[0014] In one embodiment, the outlet is elongated, the electronic outlet is slit-shaped, and the width of the electronic outlet ranges from 1 mm to 10 mm.

[0015] Another embodiment of this utility model provides an ion implantation device, including an ion source and an electron generator as described above, wherein the ion source is used to generate an ion beam and the electron generator is used to emit electrons to neutralize the ion beam.

[0016] In one embodiment, the ion implantation device further includes a neutralization cavity connected to the electron generator, the neutralization cavity including a through-hole corresponding to the electron outlet, wherein the ion beam generated by the ion source neutralizes the electrons emitted by the electron generator in the neutralization cavity.

[0017] The electron generator of this embodiment uses an exit component made of non-metallic conductor material, which can avoid electron bombardment of the exit component and cause metal contamination to the ion beam, thereby improving the product yield. Attached Figure Description

[0018] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0019] Figure 1 This is a schematic diagram of an electron generator in related technologies;

[0020] Figure 2 This is a schematic diagram of an electronic generator according to an embodiment of the present invention;

[0021] Figure 3 This is an assembly diagram of an electronic generator according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the neutralization of an electron beam and an ion beam in a neutralization cavity according to an embodiment of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model more apparent, exemplary embodiments according to this utility model will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this utility model, and not all embodiments of this utility model. It should be understood that this utility model is not limited to the exemplary embodiments described herein. Based on the embodiments of this utility model described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of this utility model.

[0024] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0025] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art.

[0026] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0027] To fully understand this utility model, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this utility model. Optional embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0028] like Figure 1 As shown, conventional electron generators typically have two outlets 102 on the reaction chamber 101. An electron outlet is located in the middle of the outlet 102, and the outlet 102 is made of metal. The two outlets 102 are centrally located, and the distance between them is approximately 100 mm.

[0029] The electron generator has two main problems: First, the electrons bombard the exit component 102, causing metal consumption. Ion implantation equipment changes the conductivity at the target depth of the wafer through ion doping. If there is metal contamination in the ion beam, the ion implantation depth and conductivity will become uncontrollable, affecting product yield. Second, the two exit components 102 are arranged in the middle, which can easily lead to poor uniformity of the ion beam near the electron exit and far from the exit component. Differences in ion beam uniformity will lead to differences in the number of ion dopants on the wafer surface, resulting in different conductivity in different areas, ultimately affecting product yield.

[0030] To address the aforementioned technical problems, this utility model provides an electron generator, as described above. Figure 2 and Figure 3 The electron generator of this utility model embodiment includes: a reaction chamber 201, which is connected to a gas source and a radio frequency power supply, and is used to generate a radio frequency electric field under the action of the radio frequency power supply, and to dissociate the gas from the gas source through the radio frequency electric field to generate electrons; an outlet 202, which is disposed on the reaction chamber 201, and has an electron outlet 203 connected to the inside of the reaction chamber 201 in the middle, through which electrons inside the reaction chamber 201 overflow, and the material of the outlet 202 is a non-metallic conductor.

[0031] Exemplarily, the reaction chamber 201 includes a gas inlet and at least two electrode plates disposed opposite each other. The gas inlet is connected to a gas source for obtaining gas supplied by the gas source; the gas may include an inert gas, such as xenon or argon. The electrode plates are electrically connected to a radio frequency (RF) power supply for generating a high-frequency converted electric field under the action of the RF power supply. The gas entering the reaction chamber 201 oscillates under the action of the RF electric field. When the oscillation force is greater than the bonding force, electrons in the gas dissociate. When the ion beam passes through the electron generator, it exerts a pulling force on the electrons, causing the electrons in the reaction chamber 201 to overflow from the electron outlet 203 in the middle of the outlet 202, thereby neutralizing the ion beam.

[0032] As mentioned above, the exit component of conventional electron generators is made of aluminum. Electron bombardment of the exit component results in aluminum consumption, contaminating the process and the wafer, thus affecting product yield. To avoid this problem, this embodiment of the invention uses a non-metallic conductor as the exit component 202, thereby preventing metal contamination at the source.

[0033] For example, the non-metallic conductor constituting the outlet component 202 may include graphite, which is a stable material with good conductivity, and can avoid affecting the radio frequency electric field while avoiding metal contamination.

[0034] See Figure 3The outlet component 202 is fixed to the reaction chamber 201 by screws 204. While conventional screws are typically made of aluminum, in this embodiment, to further avoid metal contamination, non-metallic screws 204 are used to fix the outlet component 202. The screws 204 may be made of materials including, but not limited to, graphite.

[0035] Furthermore, conventional electron generators typically have two electron outlets, resulting in varying degrees of electron neutralization of the ion beam at different locations, with the uniformity of the ion beam decreasing further away from the electron outlet. To address this issue, the electron generator of this embodiment includes at least three outlet elements 202 arranged at intervals, with the electron outlets 203 being orifice-shaped. Exemplarily, the outlet elements 202 can be circular, square, or triangular, and the electron outlets 203 can be circular, directional, or triangular orifices. By increasing the number of electron outlets 203, the ion beam can be neutralized more uniformly throughout, and the ion beam can be more evenly focused as it passes beneath the electron generator due to the principle of opposite poles attracting.

[0036] For example, at least three exit elements 202 are of the same size and arranged at equal intervals to further improve the uniformity of the ion beam. The distance between the exit elements 202 and the edge of the electron generator is equal to the spacing between the exit elements 202. Taking four exit elements 202 as an example, when the size of the electron generator along the arrangement direction of the exit elements 202 is 470 mm, the distance D1 between the exit elements 202 and the distance D1 between the exit elements 202 and the edge of the electron generator are both 94 mm.

[0037] In another example, the outlet component 202 is elongated, and the provided electronic outlet 203 is slit-shaped. The dimensions of the outlet component 202 and the electronic outlet 203 along the length direction of the electron generator are greater than their dimensions along the width direction of the electron generator. Exemplarily, the dimension of the electronic outlet 203 along the length direction of the electron generator is not less than half the length of the electron generator.

[0038] Furthermore, this embodiment of the invention also increases the aperture of the electron outlet 203. Specifically, when the electron outlet 203 is hole-shaped, its width can be increased to 0.3mm to 1.5mm. When the electron outlet 203 is slit-shaped, its width can be increased to 1mm-10mm. The length of the slit-shaped electron outlet 203 can essentially penetrate the entire electron generator, with a length range between 440mm and 470mm. Increasing the aperture of the electron outlet 203 results in more electrons overflowing, which can better neutralize the ion beam and the electrical properties of the wafer surface.

[0039] Furthermore, this embodiment of the invention also increases the thickness of the outlet component 202, specifically increasing it to 2mm-3mm, for example, to 2.2mm. Using a thicker outlet component 202 helps extend its service life.

[0040] Based on the above description, the electron generator of this utility model uses a non-metallic conductor as the outlet component 202, which can avoid the damage to parts or metal contamination caused by electron bombardment of the outlet component 202; setting multiple electron outlets or slit-shaped electron outlets can improve the uniformity of the ion beam.

[0041] Another embodiment of this utility model provides an ion implantation device, including an ion source and an electron generator as described above. The ion source is used to generate an ion beam, and the electron generator is used to emit electrons to neutralize the ion beam. Specifically, when the ions generated by the ion source pass through the electron generator, they exert an attractive force on the electrons in the electron generator, causing the electrons to overflow through the electron outlet, thereby neutralizing the ion beam.

[0042] For example, such as Figure 4 As shown, the ion implantation device also includes a neutralization cavity 300 connected to the electron generator 200. The neutralization cavity 300 has a ring-shaped structure, and the ion beam passes through the neutralization cavity 300 in a direction perpendicular to the plane of the ring. The neutralization cavity 300 includes through-holes corresponding to the electron outlets. Electrons emitted by the electron generator 200 are emitted into the neutralization cavity 300 through the through-holes, and the plane containing the electron beam is substantially perpendicular to the plane containing the ion beam. The ion beam generated by the ion source and the electrons emitted by the electron generator 200 are neutralized in the neutralization cavity 300. For example, when the electron generator 200 includes four electron outlets, the neutralization cavity is provided with four through-holes accordingly. Increasing the number of through-holes improves the neutralization effect and uniformity of the ion beam.

[0043] For example, in addition to the ion source and electron generator, the ion implantation device also includes an extraction electrode, an ion analyzer, an accelerating tube, a process chamber, etc.

[0044] Specifically, during ion implantation, the ion source ionizes the dopant to obtain an ion beam. The ion beam is then extracted from the ion source under the influence of a negative voltage provided by the extraction electrode.

[0045] The extracted ion beam then enters the ion analyzer. Based on the principle that ions of different masses and charges will undergo circular arc motions of different curvatures when passing through a magnetic field due to electromagnetic force, the ion analyzer can separate the desired ions from the mixed ion beam.

[0046] After leaving the ion analyzer, the ion beam enters the accelerating tube. The accelerating tube is a linear design with annular electrodes arranged along the axial direction. Each electrode is negatively charged, and the charge increases along the direction of the accelerating tube. The accelerating tube can accelerate the injected ions to the required speed.

[0047] An electron generator is located at the rear end of the accelerating tube and is used to generate an electron beam to neutralize the accelerated ion beam. The electron generator is connected to a process chamber, which is used to implant ions into the wafer. Exemplarily, the process chamber includes a scanning device, a terminal stage for loading and unloading silicon wafers, and a wafer transport device, etc.

[0048] The ion implantation device of this utility model includes the above-mentioned electron generator, which emits an ion beam with less metal contamination and better uniformity, thereby improving the quality of semiconductor devices.

[0049] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

[0050] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention.

[0051] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0052] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the present invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0053] Similarly, it should be understood that, in order to simplify the present invention and aid in understanding one or more aspects of the various inventions, in the description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of the present invention should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its novelty lies in the fact that the corresponding technical problem can be solved with fewer features than all of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the present invention.

[0054] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0055] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0056] The various component embodiments of this utility model can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to embodiments of this utility model. This utility model can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such an implementation of this utility model can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0057] It should be noted that the above embodiments are illustrative of the present invention and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The present invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. An electron generator, characterized in that, The electron generator includes: A reaction chamber is connected to a gas source and a radio frequency power supply. It is used to generate a radio frequency electric field under the action of the radio frequency power supply, and to dissociate the gas from the gas source through the radio frequency electric field to generate electrons. An outlet component is disposed on the reaction chamber. An electron outlet connected to the interior of the reaction chamber is provided in the middle of the outlet component. Electrons inside the reaction chamber overflow through the electron outlet. The outlet component is made of a non-metallic conductor. The outlet component is fixed to the reaction chamber by screws, and the screws are made of a non-metallic conductor. Wherein, the electronic outlet is hole-shaped and the outlet component is circular; or, the electronic outlet is slit-shaped and the outlet component is elongated.

2. The electron generator as described in claim 1, characterized in that, The material of the exported component includes graphite.

3. The electron generator as described in claim 1, characterized in that, The screw is made of graphite.

4. The electron generator as described in claim 1, characterized in that, When the electron outlet is hole-shaped, the electron generator includes at least three outlet elements arranged at intervals.

5. The electron generator as described in claim 4, characterized in that, The at least three export components are of the same size and are arranged at equal intervals.

6. The electron generator as described in claim 4, characterized in that, The width of the electronic outlet ranges from 0.3 mm to 1.5 mm.

7. The electron generator as described in claim 1, characterized in that, When the electronic outlet is slit-shaped, the width of the electronic outlet ranges from 1 mm to 10 mm.

8. An ion implantation device, characterized in that, It includes an ion source and an electron generator as described in any one of claims 1-7, the ion source being used to generate an ion beam and the electron generator being used to emit electrons to neutralize the ion beam.

9. The ion implantation apparatus as described in claim 8, characterized in that, It also includes a neutralization cavity connected to the electron generator, the neutralization cavity including a through hole corresponding to the electron outlet, wherein the ion beam generated by the ion source and the electrons emitted by the electron generator are neutralized in the neutralization cavity.

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