Ion implanter

Abstract

The utility model provides an ion implanter, which comprises a shell provided with a processing chamber and a shielding plate arranged at the bottom of the processing chamber and used for bearing residues; the gas supply device is arranged in the shell in a penetrating manner, communicates with the processing cavity and provides a gas supply channel for the protective gas to pass through; the ionization cavity is arranged in the processing cavity, is communicated with a gas outlet port of the gas supply channel, is used for carrying out ionization treatment on the protective gas and generating target ions, and is positioned above the shielding plate; and the power supply device is arranged in the processing cavity, is electrically connected with the ionization cavity, and provides driving voltage for the ionization cavity, so that the ionization cavity sprays the target ions to the processing cavity. By adopting the technical scheme, the cleanliness in the processing cavity can be improved.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, and in particular to an ion implanter. Background Technology

[0002] Ion implantation is a key process widely used in semiconductor manufacturing, materials science, and surface engineering. By accelerating and implanting ions into the medium to be treated, the physical and chemical properties of the medium can be effectively altered, thereby achieving various functions such as doping, modification, and surface treatment.

[0003] Currently, after an ion implantation is completed, residue remains in the processing chamber. If not removed promptly, this residue will evaporate upon heating during the next ion implantation, contaminating the ions in that subsequent implantation process. Therefore, before performing the next ion implantation, the inner wall of the processing chamber is typically bombarded with an argon ion beam to remove the residue.

[0004] However, the cleaning methods described above are ineffective and cannot completely remove residues. Therefore, providing a technical solution to improve the cleanliness of the processing chamber has become a pressing technical problem for those skilled in the art. Utility Model Content

[0005] In view of this, the present invention provides an ion implanter that can improve the cleanliness of the processing chamber.

[0006] This utility model provides an ion implanter, comprising: a housing having a processing chamber and a shielding plate disposed at the bottom of the processing chamber for carrying residues; a gas supply channel provided through the housing and communicating with the processing chamber for the passage of protective gas; an ionization chamber disposed within the processing chamber and communicating with the outlet port of the gas supply channel for ionizing the protective gas to generate target ions, the ionization chamber being located above the shielding plate; and a power supply device disposed within the processing chamber and electrically connected to the ionization chamber for providing a driving voltage to the ionization chamber, thereby causing the ionization chamber to spray the target ions into the processing chamber.

[0007] Optionally, the ion implanter further includes: a gas supply device connected to the gas supply channel inlet port for providing the protective gas, wherein the gas supply device stores multiple different types of protective gases, and the type and flow rate of the protective gas provided by the gas supply device are determined according to the type and amount of the residue.

[0008] Optionally, the number of gas supply channels is multiple;

[0009] The gas supply device includes: a plurality of gas supply units for storing the protective gas, wherein one of the gas supply units stores one type of protective gas and is connected to a gas supply channel;

[0010] A first switch is disposed between the gas supply unit and the gas supply channel inlet port for selecting the passage between the gas supply unit and the gas supply channel; wherein the gas supplied by the gas supply unit in the selected state is the protective gas.

[0011] Optionally, the shielding plate includes a substrate and protruding members disposed on the substrate.

[0012] Optionally, the cross-section of the protruding member is a hyperbola with an inwardly concave shape, wherein the cross-section is a plane perpendicular to the surface of the substrate.

[0013] Optionally, the shielding plate and the processing chamber are detachably connected.

[0014] Optionally, the power supply device includes:

[0015] power supply;

[0016] Multiple transformer branches are disposed between the power supply and the ionization cavity to change the driving voltage output to the ionization cavity, and each transformer branch has a different transformation ratio.

[0017] Optionally, each transformer branch includes a second switch, a first resistor, and a second resistor disposed between the power supply and the ionization cavity. The first end of the second switch is electrically connected to the power supply, the second end of the second switch is electrically connected to the first end of the first resistor, the second end of the first resistor is electrically connected to the first end of the second resistor and the ionization cavity, and the second end of the second resistor is grounded.

[0018] Optionally, the ion implanter further includes: a vacuum pump disposed on the outer wall of the housing, a gas extraction pipe provided on one side of the vacuum pump, and a gas storage device connected to the gas extraction pipe.

[0019] Optionally, the ion implanter further includes a heating device disposed within the processing chamber and located between the gas supply channel and the ionization chamber, for heating the protective gas.

[0020] Compared with the prior art, the technical solution of this utility model embodiment has the following advantages:

[0021] Using the ion implanter provided by this invention, the ionization chamber can ionize the introduced protective gas to generate target ions. Since the ionization chamber is located above the shielding plate, when the target ions are sprayed into the processing chamber, the target ions can scatter on the shielding plate. During the falling process of the target ions, they can drive the residual gas in the processing chamber to move downwards and form a covering layer on the shielding plate to cover the residues already present on the shielding plate. In this way, the cleaning operation can be completed by directly removing the shielding plate, and the covered residues are not easy to fall off, thus improving the cleanliness of the processing chamber. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of an ion implanter according to the first embodiment of the present invention is shown;

[0024] Figure 2 A schematic diagram illustrating the residue removal principle in an embodiment of this utility model is shown;

[0025] Figure 3 A schematic diagram of an ion implanter according to the second embodiment of the present invention is shown. Detailed Implementation

[0026] The technical solutions of this utility model will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of this utility model, used to illustrate the concept of this utility model; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of this utility model. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0027] The accompanying drawings in this embodiment are schematic diagrams used to illustrate the concept of this utility model, and to schematically show the shapes of the various parts and their interrelationships. It should be understood that, in order to clearly show the structure of the various components of this utility model, the drawings are not drawn to the same scale, and the same reference numerals are used to indicate the same parts in the drawings.

[0028] As described in the background section, the cleaning effect of the existing cleaning methods is not good and cannot completely remove the residues. This is because the current cleaning methods use Ar to purge the processing chamber. In this process, the diffused gas in the processing chamber can be removed, but other residues already present in the processing chamber cannot be covered, isolated or removed. As a result, when the processing chamber is opened, the residues may overflow to the outside of the processing chamber, causing other damage, or the residues may still exist in the processing chamber.

[0029] To address the aforementioned technical problems, this embodiment provides an ion implanter, comprising: a housing having a processing chamber and a shielding plate disposed at the bottom of the processing chamber to carry residues; a gas supply channel provided through the housing and communicating with the processing chamber for the passage of protective gas; an ionization chamber disposed within the processing chamber and communicating with the outlet port of the gas supply channel for ionizing the protective gas to generate target ions, the ionization chamber being located above the shielding plate; and a power supply device disposed within the processing chamber and electrically connected to the ionization chamber for providing a driving voltage to the ionization chamber, thereby causing the ionization chamber to spray the target ions into the processing chamber.

[0030] Using the ion implanter in this embodiment, the ionization chamber can ionize the introduced protective gas to generate target ions. Since the ionization chamber is located above the shielding plate, when the target ions are sprayed into the processing chamber, the target ions can scatter on the shielding plate. During the falling process of the target ions, they can drive the residual gas in the processing chamber to move downwards and form a covering layer on the shielding plate to cover the residues already present on the shielding plate. In this way, the cleaning operation can be completed by directly removing the shielding plate, and the covered residues are not easy to fall off, thus improving the cleanliness of the processing chamber.

[0031] Furthermore, during the removal of the shielding plate, the residue will not come into direct contact with the air or the operator due to the coverage effect of the target ions, thus reducing contamination and improving operational safety.

[0032] To enable those skilled in the art to have a clearer understanding of the technical concept, technical principle, advantages, etc. contained in the embodiments of this utility model, a detailed description is provided below with reference to the accompanying drawings, through specific embodiments, and in conjunction with specific application scenarios.

[0033] See Figure 1 The diagram shown below illustrates the structure of an ion implanter according to the first embodiment of this invention. Figure 1 As shown, the ion implanter may include: a housing 10 having a processing chamber 12, and a container disposed at the bottom of the processing chamber 12 to hold residue R (see Figure 2The shielding plate 20; passing through the housing 10 and communicating with the processing chamber 12, providing a gas supply channel 30 for the protective gas to pass through; disposed in the processing chamber 12 and communicating with the gas outlet port of the gas supply channel 30, ionizing the protective gas to generate target ions (see...). Figure 1 The ionization cavity 40 (shown as a line segment in the diagram) is located above the shielding plate 20; it is disposed within the processing chamber 12 and electrically connected to the ionization cavity 40, providing a driving voltage to the ionization cavity 40 so that the ionization cavity 40 sprays (e.g., ...) into the processing chamber 12. Figure 1 The power supply device for the target ion (shown by the middle arrow) is not shown in the figure.

[0034] The housing 10 is used to provide a closed process space for the ionization and cleaning processes. By performing the cleaning process in the closed process space, the risk of residue (e.g., residual gas) spillage can be reduced, thereby further improving the cleaning effect.

[0035] In this embodiment, the shell 10 is cylindrical in shape. The cylindrical structure may include at least one of a cylindrical structure, an elliptical cylindrical structure, and a square cylindrical structure. This embodiment of the present invention does not limit the shell structure, and those skilled in the art can adjust and set it according to the actual situation.

[0036] The shielding plate 20 is used to isolate the space between the residue R and the bottom of the processing chamber 12, so that the residue R can be completely covered on the shielding plate 20.

[0037] In this embodiment, the shielding plate 20 may include a substrate 22 and a protruding member 24 disposed on the substrate 22.

[0038] The two ends of the substrate 22 are in contact with the sidewalls of the processing chamber 12 to achieve a tight bond between the shielding plate 20 and the processing chamber 12; and the substrate 22 can serve as a support so that the covered residue R can be better contained.

[0039] The protruding member 24 can serve to accommodate the residue R, thereby reducing the slippage of the residue R when the shielding plate 20 is removed (as a non-limiting example, the residue R slips in a direction parallel to the surface of the substrate 22), thus improving the cleaning effect.

[0040] In this embodiment, the cross-section of the protruding member 24 is a hyperbola with an inwardly concave shape, wherein the cross-section is a plane perpendicular to the surface of the substrate 22.

[0041] The concave hyperbolic shape allows the protruding member 24 and the substrate 22 to form a larger accommodating space, thereby allowing more residue R to be accommodated within the concave hyperbolic shape. This further reduces the risk of residue R slipping out, resulting in better cleaning performance.

[0042] It should be noted that, firstly, there are multiple protruding members 24, and these protruding members 24 can be evenly distributed on the substrate 22 or randomly distributed on the substrate 22. This invention does not impose requirements on the distribution position of the protruding members 24; secondly, the protruding members can also be other types of structures with internal recesses. Figure 1 The structure of the protruding component shown is for illustrative purposes only.

[0043] The gas supply channel 30 is used to transmit the protective gas required for cleaning to the ionization chamber 40. The gas transmission principle and structure of the gas supply channel 30 can be found in the description of existing solutions.

[0044] The ionization chamber 40 serves to ionize the protective gas. By ionizing the protective gas, the target ions TG can be obtained to cover the residue R.

[0045] The generation process of the target ion TG can be as follows: when the protective gas is transported to the ionization chamber, the protective gas is excited by a high-energy electron beam or electric field, thereby ionizing the protective gas and releasing the ions therein.

[0046] The power supply device provides a bias voltage to the ionization chamber 40. Under the action of this bias voltage, the target ions in the ionization chamber 40 can be drawn out, so that the target ions TG can be sprayed into the entire processing chamber 12 to carry and cover the residue R in the processing chamber 12.

[0047] More specifically, see Figure 2 The schematic diagram shown in this embodiment of the present invention illustrates a principle for residue removal. After the low-energy target ion TG contacts the processing chamber 12, it deposits as a stable covering layer, covering the residue R. This allows the residue R to be contained between the target ion TG and the shielding plate 20. Since the shielding plate 20 and the processing chamber 12 are detachably connected, the processing chamber 12 can be opened directly during maintenance, and the shielding plate 20 can be removed to remove the residue R.

[0048] As a specific embodiment, the introduced gas can be SiH4, which, after being treated in the ionization chamber, can form free silicon ions. When a driving voltage is applied, the free silicon ions will be attracted and scattered throughout the processing chamber.

[0049] Low-energy free silicon ions deposit into the processing chamber after contacting it, forming a stable silicon capping layer that covers the residue.

[0050] In this embodiment, the power supply device may include: a power supply; and multiple transformer branches disposed between the power supply and the ionization cavity to change the driving voltage output to the ionization cavity, wherein each transformer branch has a different transformation ratio.

[0051] Specifically, the power supply can provide an initial reference voltage. Considering the variation in the driving voltage required by the ionization cavity, multiple transformer branches with different duty cycles are set up so that the driving voltage after transformation by the transformer branches is different. In this way, according to the actual application requirements, different driving voltages can be provided to the ionization cavity by selecting different transformer branches, thereby changing the transport rate of the target ions.

[0052] In this embodiment, each transformer branch adopts the same structure, the difference being that the voltage division ratio of each transformer branch is different.

[0053] Furthermore, the transformer branch may include a second switch, a first resistor, and a second resistor disposed between the power supply and the ionization cavity, wherein the first end of the second switch is electrically connected to the power supply, the second end of the second switch is electrically connected to the first end of the first resistor, the second end of the first resistor is electrically connected to the first end of the second resistor and the ionization cavity respectively, and the second end of the second resistor is grounded.

[0054] Specifically, the first resistor and the second resistor determine the voltage division ratio of the voltage divider branch. By selecting different switches, transformer branches with corresponding duty cycles can be used to provide different driving voltages for the ionization cavity.

[0055] In this embodiment, the driving voltage can refer to the voltage drop across the second resistor.

[0056] It should be noted that in some other embodiments, other methods can be used to make the driving voltage value output to the ionization cavity different. The above example is only a feasible example and does not mean that the driving voltage value can only be changed by resistor voltage division. For example, in some embodiments, multiple different voltage sources can be set, and each voltage source and the ionization cavity have a switch. By selecting the switch, the corresponding voltage source is connected to the ionization cavity.

[0057] In the actual cleaning process, the inventors further discovered that the chemical properties of different residues R vary greatly. If the same protective gas is used, some types of residues R cannot be removed or cannot be completely removed. Alternatively, for the same residue R, different amounts of residue R require different protective gases.

[0058] Therefore, to adapt to different residue removal scenarios, see [link / reference]. Figure 3The schematic diagram of an ion implanter in the second embodiment of the present invention shown is provided. The ion implanter may further include: a gas supply device 50 connected to the gas inlet port of the gas supply channel 30 to provide the protective gas. The gas supply device 50 stores a variety of different types of protective gases, and the type and flow rate of the protective gas provided by the gas supply device 50 are determined according to the type and amount of the residue R.

[0059] Specifically, when a cleaning operation is required, the type and amount of residue R can be determined. The controller can then generate a signal to control the gas supply device 50 to supply gas based on the type and amount of residue R. Since the gas supply device 50 stores various types of protective gases, in cooperation with the controller and the gas supply device 50, a solution compatible with the type of residue R and the flow rate of the protective gas can be provided to the ionization chamber through the gas supply channel 30. This effectively removes residue R without requiring frequent replacement of the gas supply channel 30, improving the flexibility and versatility of the ion implanter.

[0060] In this embodiment, see Figure 3 The number of gas supply channels 30 is multiple (as a non-limiting example, the number of gas supply channels 30 is 3, such as gas supply channels 301, 302 and 303), wherein different gas supply channels 30 are used to supply different protective gases, which can avoid cross-mixing between different protective gases and improve the cleaning effect; or the same gas supply channel 30 is used to supply protective gases with similar properties, so as to reduce the number of gas supply channels 30.

[0061] Accordingly, the gas supply device 50 may include: a plurality of gas supply units for storing the protective gas (as a non-limiting example, the number of gas supply units is three, such as gas supply units SP1, SP2 and SP3), and one of the gas supply units stores one type of protective gas and is connected to a gas supply channel (as a non-limiting example, gas supply channel 301 is connected to gas supply unit SP1, gas supply channel 302 is connected to gas supply unit SP2, and gas supply channel 303 is connected to gas supply unit SP3);

[0062] A first switch is disposed between the gas supply unit and the gas supply channel inlet port for selecting the passage between the gas supply unit and the gas supply channel (as a non-limiting example, the number of first switches is three, such as first switches K1, K2 and K3, and first switch K1 is disposed between gas supply channel 301 and gas supply unit SP1, first switch K2 is disposed between gas supply channel 302 and gas supply unit SP2, and first switch K3 is disposed between gas supply channel 303 and gas supply unit SP3); wherein, the gas supplied by the gas supply unit in the selected state is the protective gas.

[0063] Specifically, the type of protective gas stored in the gas supply section is known. When the processing chamber 12 needs to be processed, depending on the type of residue in the processing chamber 12, one of the first switches can be turned on. For example, the first switch K1 can be turned on, thereby opening the transmission path between the gas supply section SP1 and the gas supply channel 301. Thus, the protective gas in the gas supply section SP1 can be transmitted to the ionization chamber 40 to cover the residue on the shielding plate 20.

[0064] Furthermore, depending on the amount of residue in the processing chamber 12, the dosage of protective gas that matches the amount of residue can be supplied to the processing chamber 12 by increasing the opening degree of the first switch K1 or extending the opening time of the first switch K1, so that the protective gas can completely cover the residue.

[0065] In this embodiment, the first switch can be a one-way valve. By using a one-way valve as the first switch, the protective gas can only be transmitted along the gas supply channel toward the ionization chamber and will not flow back into the gas supply section, which improves the transmission efficiency of the protective gas.

[0066] Understandably, firstly, Figure 3 The number of the first switch, gas supply unit, and gas supply channel shown is merely illustrative and is used to illustrate the use of a first switch, gas supply unit, and gas supply channel with a cooperative relationship to achieve the transmission process of different protective gases. It should not be construed as a limitation on this utility model. Secondly, the type of the first switch is also illustrative. In some other embodiments, the first switch can be a solenoid valve, a manual valve, etc.

[0067] In this embodiment, there is a situation where the processing chamber is filled with a lot of protective gas due to excessive protective gas or insufficient ionization of the protective gas in the ionization chamber. Based on this, the ion implanter also includes: a vacuum pump disposed on the outer wall of the housing, a gas extraction pipe disposed on one side of the vacuum pump, and a gas storage device connected to the gas extraction pipe.

[0068] In other words, when the protective gas is transported to the ionization chamber in time enough to completely cover the residue, the vacuum pump can be activated to extract the protective gas that has not been fully ionized in the processing chamber. The unionized protective gas is then stored through the extraction pipe, thereby enabling the recycling of the protective gas and reducing cleaning costs.

[0069] In this embodiment, the ion implanter further includes a heating device disposed in the processing chamber and located between the gas supply channel and the ionization chamber, for heating the protective gas.

[0070] By setting up a heating device, initial energy can be provided to the protective gas, reducing the difficulty of ionization of the protective gas, thereby shortening the time for forming target ions and improving cleaning efficiency.

[0071] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0072] While this embodiment has been disclosed above, the utility model is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of this utility model; therefore, the scope of protection of this utility model should be determined by the scope defined in the claims.

Claims

1. An ion implanter, characterized in that, include: The housing has a processing chamber and a shielding plate disposed at the bottom of the processing chamber to carry residues; It passes through the housing and communicates with the processing chamber, providing a gas supply channel for the protective gas to pass through; The ionization chamber is located above the shielding plate and is connected to the outlet port of the gas supply channel. It is set inside the processing chamber and connected to the outlet port of the gas supply channel to ionize the protective gas and generate target ions. A power supply device disposed within the processing chamber and electrically connected to the ionization chamber, providing a driving voltage to the ionization chamber so that the ionization chamber sprays the target ions into the processing chamber.

2. The ion implanter according to claim 1, characterized in that, The ion implanter also includes: A gas supply device is connected to the gas inlet port of the gas supply channel to provide the protective gas. The gas supply device stores multiple different types of protective gases, and the type and flow rate of the protective gas provided by the gas supply device are determined according to the type and amount of the residue.

3. The ion implanter according to claim 2, characterized in that, The number of gas supply channels is multiple; The gas supply device includes: Multiple gas supply units for storing the protective gas, wherein one of the gas supply units stores one type of protective gas and is connected to a gas supply channel; A first switch is disposed between the gas supply unit and the gas supply channel inlet port for selecting the passage between the gas supply unit and the gas supply channel; wherein the gas supplied by the gas supply unit in the selected state is the protective gas.

4. The ion implanter according to claim 1, characterized in that, The shielding plate includes a base plate and protruding members disposed on the base plate.

5. The ion implanter according to claim 4, characterized in that, The protruding member has an inwardly concave hyperbola-shaped cross section, wherein the cross section is a plane perpendicular to the surface of the substrate.

6. The ion implanter according to claim 1, characterized in that, The shielding plate and the processing chamber are detachably connected.

7. The ion implanter according to claim 1, characterized in that, The power supply device includes: power supply; Multiple transformer branches are disposed between the power supply and the ionization cavity to change the driving voltage output to the ionization cavity, and each transformer branch has a different transformation ratio.

8. The ion implanter according to claim 7, characterized in that, Each transformer branch includes a second switch, a first resistor, and a second resistor disposed between the power supply and the ionization cavity. The first end of the second switch is electrically connected to the power supply, the second end of the second switch is electrically connected to the first end of the first resistor, the second end of the first resistor is electrically connected to the first end of the second resistor and the ionization cavity, and the second end of the second resistor is grounded.

9. The ion implanter according to claim 1, characterized in that, The ion implanter further includes: a vacuum pump disposed on the outer wall of the housing, a gas extraction pipe provided on one side of the vacuum pump, and a gas storage device connected to the gas extraction pipe.

10. The ion implanter according to claim 1, characterized in that, The ion implanter also includes: A heating device disposed within the processing chamber and located between the gas supply channel and the ionization chamber to heat the protective gas.

Images