An etching apparatus for an MRAM memory

Abstract

This application discloses an etching apparatus for an MRAM memory, comprising: an ion source, a neutralizer, and a stage. The neutralizer is disposed at the exit port of the ion source, and the stage is disposed on one side of the ion source for receiving plasma emitted from the ion source. The stage includes a pressure ring and at least one electrode on its incident surface. Both the pressure ring and the at least one electrode are disposed at the edge of the stage, and the at least one electrode is embedded inside or around the pressure ring. The at least one electrode is connected to a radio frequency generator via a wire. By adjusting the stage angle within the IBE etching chamber, etching of the MRAM memory cell and sidewall cleaning can be completed within the same chamber, facilitating multiple switching operations. By embedding at least one electrode at the edge of the stage and applying power control to each electrode, the plasma distribution on the stage can be adjusted in zones, improving etching uniformity.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and more particularly to an etching apparatus for an MRAM memory. Background Technology

[0002] Magnetic random access memory (MRAM) is a non-volatile memory characterized by high-speed read / write capabilities and high integration density. Current MRAM device etching processes involve first etching in an ICP chamber, then transferring the device to an IBE chamber for sidewall bombardment cleaning. This requires switching between different chambers, making the fabrication process very cumbersome.

[0003] Typically, in an ICP chamber, the top gas spray head also serves as the upper electrode, the center electrode of the base is connected to the first RF power supply, and the edge of the base is connected to the second RF power supply to compensate for edge effects. Because the plasma is controlled by an electric field during etching, and the field strength at the edges is easily affected by external factors, this leads to uneven plasma concentration and energy, resulting in a ring of unevenly etched areas in the produced semiconductor devices. With the continuous increase in process technology, poor uniformity at the edges causes a significant decrease in yield, resulting in substantial losses for semiconductor devices. Summary of the Invention

[0004] This application provides an etching apparatus for an MRAM memory that can solve the problem of uneven edge etching.

[0005] An etching apparatus for an MRAM memory includes: an ion source, a neutralizer, and a stage, wherein:

[0006] The neutralizer is disposed at the outlet of the ion source, and the stage is disposed on the side of the ion source outlet to receive the plasma emitted by the ion source.

[0007] The stage includes a pressure ring and at least one electrode on its incident surface end face. The pressure ring and the at least one electrode are both disposed on the edge of the stage, and the at least one electrode is embedded inside the pressure ring or outside the pressure ring.

[0008] The at least one electrode is connected to the radio frequency generator via a wire.

[0009] In one optional design, the stage is set at a preset angle to the direction of plasma transmission emitted from the ion source, wherein the preset angle is greater than 0° and less than 180°, and the preset angle is adjustable.

[0010] In an alternative design, a power divider is also included, wherein,

[0011] The power divider is disposed between the at least one electrode and the radio frequency generator and is used to regulate the current entering the at least one electrode.

[0012] In one alternative design, the frequency of the radio frequency generator is greater than 13.56 MHz.

[0013] In one alternative design, the pressure ring is made of a material with a relatively low permittivity or an insulating material.

[0014] In an alternative design, the at least one electrode is connected to the radio frequency generator via a wire, including:

[0015] Each of the at least one electrode is connected to the same radio frequency generator; or...

[0016] Each of the at least one electrodes is connected to a different radio frequency generator.

[0017] In one optional embodiment, the system further includes a cavity in which the ion source, the neutralizer, and the stage are disposed for etching and sidewall cleaning.

[0018] This application provides an etching apparatus for an MRAM memory. The apparatus includes an ion source, a neutralizer, and a stage. The neutralizer is disposed at the exit port of the ion source, and the stage is disposed on one side of the ion source for receiving the plasma emitted from the ion source. The stage includes a pressure ring and at least one electrode on its incident surface. Both the pressure ring and the at least one electrode are disposed at the edge of the stage, and the at least one electrode is embedded inside or outside the pressure ring. The at least one electrode is connected to a radio frequency generator via a wire. By setting a pressure ring and at least one electrode on the stage and applying different power controls to each, the plasma distribution on the stage can be adjusted in zones, improving the uniformity of etching. Furthermore, etching and sidewall cleaning can be completed in the same chamber, facilitating multiple switching operations. Attached Figure Description

[0019] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This application provides a structural diagram of an etching apparatus for an MRAM memory.

[0021] Figure 2 These are schematic diagrams of two platform structures provided in the embodiments of this application.

[0022] Figures 1 to 2 The components indicated by the numbers are: 1 ion source, 2 neutralizer, 3 stage, 4 pressure ring, and 5 electrode. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings.

[0024] The terminology used in the following embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to include the plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that although the terms first, second, etc., may be used in the following embodiments to describe a class of objects, the objects are not limited to these terms. These terms are only used to distinguish specific objects of that class of objects. Other classes of objects that may be described using the terms first, second, etc. in the following embodiments are similarly not described here.

[0025] This application relates to the field of semiconductor technology. Edge effects during etching processes have long been a problem plaguing the semiconductor industry. During etching, the plasma is controlled by an electric field, and the field strength at the edges is affected by external factors, leading to uneven plasma concentration and energy. This results in semiconductor devices exhibiting an uneven etching region, reducing semiconductor yield. To address this edge effect, this application provides an etching apparatus for MRAM memory.

[0026] The following describes an etching apparatus for an MRAM memory according to several implementation methods.

[0027] like Figure 1 As shown, Figure 1 This diagram illustrates the structure of an etching apparatus for an MRAM memory. The apparatus includes: an ion source 1, a neutralizer 2, and a stage 3, wherein:

[0028] The neutralizer 2 is disposed at the outlet of the ion source 1, and the stage 3 is disposed on the side of the ion source 1 for receiving the plasma emitted by the ion source 1.

[0029] The stage 3 includes a pressure ring 4 and at least one electrode 5 on its incident surface end face. The pressure ring 4 and the at least one electrode 5 are both disposed on the edge of the stage 3. The at least one electrode 5 is embedded inside the pressure ring 4 or outside the pressure ring 4.

[0030] The at least one electrode 5 is connected to the radio frequency generator via a wire.

[0031] In this embodiment, such as Figure 1 As shown, gas is input into ion source 1 through the gas inlet and plasma is output. The charge of the plasma is controlled by adjusting neutralizer 2, and then the plasma is incident onto stage 3. Figure 2 As shown, a pressure ring 4 is provided on the incident surface end face of the stage 3. The pressure ring 4 can concentrate plasma, thereby improving the etching efficiency at the edge position. By embedding at least one electrode 5 inside or outside the pressure ring 4 and adjusting the radio frequency current entering each electrode 5 respectively, the plasma distribution on the stage 3 can be adjusted in different regions to improve the uniformity of etching.

[0032] This application provides an etching apparatus for an MRAM memory, comprising: an ion source 1, a neutralizer 2, and a stage 3. The neutralizer 2 is disposed at the exit port of the ion source 1, and the stage 3 is disposed on the exit side of the ion source 1 to receive the plasma emitted from the ion source 1. The stage 3 includes a pressure ring 4 and at least one electrode 5 on its incident surface. Both the pressure ring 4 and the at least one electrode 5 are disposed at the edge of the stage 3, and the at least one electrode 5 is embedded inside or around the pressure ring 4. The at least one electrode 5 is connected to a radio frequency generator via a wire. By adjusting the neutralizer 2 of the ion source 1, the plasma is incompletely neutralized and presents a certain potential. Simultaneously, by applying power control to the electrode 5 embedded in the pressure ring 4, the plasma distribution on the stage 3 is adjusted in zones. The apparatus provided in this application can achieve zoned modulation of the electrode 5 under plasma energy within the IBE etching chamber, improving etching uniformity.

[0033] In one optional embodiment, the stage 3 and the plasma emitted from the ion source 1 are set at a preset angle, wherein the preset angle is greater than 0° and less than 180°, and the preset angle is adjustable.

[0034] In this embodiment, the angle of ion incidence is selected based on the etching material and the preset function of the device to compensate for the etching rate at the edge of the stage 3. Simultaneously, the etching of the MRAM memory and sidewall cleaning can be completed within the same chamber, facilitating multiple switching operations.

[0035] In an optional implementation, it further includes: a power divider, wherein,

[0036] The power divider is disposed between the at least one electrode 5 and the radio frequency generator, and is used to regulate the current entering the at least one electrode 5.

[0037] In this embodiment, the power applied to different electrodes 5 is adjusted by adjusting the power of the power distributor, and the electric field is changed according to the current in the electrode 5 so that the plasma in the edge region of the stage 3 is distributed according to a preset state, thereby making the etching more uniform and improving the edge effect.

[0038] In one alternative implementation, the frequency of the radio frequency generator is greater than 13.56 MHz.

[0039] In one optional embodiment, the pressure ring 4 is made of a material with a relatively low permittivity or an insulating material.

[0040] In this embodiment, the pressure ring 4, made of a material with a relatively low permittivity or an insulating material, is used as the ion beam focusing device. Due to the high surface resistivity of the material, charge adheres and accumulates, which increases the etching rate at the edge of the stage 3 and increases the uniformity of etching.

[0041] In one optional embodiment, the at least one electrode 5 is connected to the radio frequency generator via a wire, including:

[0042] Each of the at least one electrode 5 is connected to the same radio frequency generator; or...

[0043] Each of the at least one electrode 5 is connected to a different radio frequency generator.

[0044] In this embodiment, each of the at least one electrode 5 can be connected to the same radio frequency generator via a wire. In this case, if the current of different electrodes 5 needs to be adjusted, the power applied to different electrodes 5 needs to be adjusted by a power divider. Of course, each of the at least one electrode 5 can also be connected to different radio frequency generators. The radio frequency power of multiple electrodes 5 adjusts the plasma distribution at the edge position, which improves the etching uniformity.

[0045] In one optional embodiment, it further includes a cavity, in which the ion source 1, the neutralizer 2, and the stage 3 are disposed for etching and sidewall cleaning.

[0046] In this embodiment, by setting an ion beam focusing in the IBE etching system, and with the stage 3 angle adjustable, the etching of the MRAM memory cell and the sidewall cleaning can be completed in the same chamber, facilitating multiple switching.

[0047] like Figure 2 As shown, Figure 2 The following are schematic diagrams of two types of stage 3 structures provided in this application, taking four electrodes 5 as an example. Figure 2 The stage 3 shown on the left has four electrodes 5 embedded inside the pressure ring 4, and they are evenly distributed, as shown in the figure. Figure 2As shown on the right, the stage 3 has four electrodes 5 embedded around the periphery of the pressure ring 4. It should be noted that the number of electrodes 5 is not necessarily four; they can be other numbers or distributed in other ways along the edge of the stage 3. This embodiment does not limit this.

[0048] In summary, the etching apparatus for the MRAM memory in this embodiment completes the etching of MRAM memory cells and sidewall cleaning within the same chamber, facilitating multiple switching operations. Using a material with a low relative permittivity or an insulating material as the ion beam focusing device, the high surface resistivity of the material causes charge adhesion and accumulation. By adjusting the neutralizer 2, the plasma is not completely neutralized and maintains a certain potential. Simultaneously, by embedding at least one electrode 5 at the edge of the stage 3 and applying power control to each electrode 5, the plasma distribution on the stage 3 can be regionally adjusted. The apparatus in this embodiment can achieve regional modulation of electrode 5 under plasma energy within the IBE etching chamber, improving etching uniformity.

[0049] Although alternative embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make further changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0050] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above description is only a specific embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solution of this application should be included within the scope of protection of this invention.

Claims

1. An etching apparatus for an MRAM memory, characterized in that, The device includes: an ion source, a neutralizer, a stage, and a power divider, wherein: The ion source is used to emit plasma; The neutralizer is disposed at the outlet of the ion source, and the stage is disposed on the side of the ion source outlet to receive the plasma emitted by the ion source. By adjusting the neutralizer, the plasma is not completely neutralized and is at a certain potential; The stage includes a pressure ring and at least one electrode on its incident surface end face. The pressure ring and the at least one electrode are both disposed on the edge of the stage, and the at least one electrode is embedded inside the pressure ring or outside the pressure ring. The at least one electrode is connected to the radio frequency generator via a wire; The power divider is disposed between the at least one electrode and the radio frequency generator and is used to adjust the current entering the at least one electrode. The power applied to different electrodes is adjusted by adjusting the power of the power divider, and the electric field is changed according to the current in the electrodes so that the plasma in the edge region of the stage is distributed according to a preset state.

2. The etching apparatus for the MRAM memory as described in claim 1, characterized in that, The stage is set at a preset angle to the direction of plasma transmission emitted from the ion source, wherein the preset angle is greater than 0° and less than 180°, and the preset angle is adjustable.

3. The etching apparatus for the MRAM memory as described in claim 1, characterized in that, The frequency of the radio frequency generator is greater than 13.56MHz.

4. The etching apparatus for the MRAM memory as described in claim 1, characterized in that, The pressure ring is made of a material with a relatively low permittivity or an insulating material.

5. The etching apparatus for the MRAM memory as described in claim 1, characterized in that, The at least one electrode is connected to the radio frequency generator via a wire, including: Each of the at least one electrode is connected to the same radio frequency generator; or... Each of the at least one electrodes is connected to a different radio frequency generator.

6. The etching apparatus for the MRAM memory as described in claim 1, characterized in that, Also includes: The cavity, in which the ion source, the neutralizer, and the stage are disposed, is used to perform etching and sidewall cleaning.

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