Electrostatic chuck, processing chamber and semiconductor processing equipment

Abstract

The present invention discloses an electrostatic chuck, a processing chamber and a semiconductor processing device, which relate to the field of semiconductor technology and are used to maintain a constant temperature of a wafer reacting to plasma in a plasma etching or deposition process, thereby improving the yield of the wafer. The electrostatic chuck comprises: an electrostatic chuck body, an electrostatic adsorption portion and a cooling laser. The electrostatic chuck body has a receiving cavity. The electrostatic adsorption portion is located on the surface of the electrostatic chuck body close to the wafer, and is used to fix the wafer. The cooling laser is arranged in the receiving cavity, and is used to emit a cooling laser to the electrostatic adsorption portion to cool the wafer fixed on the electrostatic adsorption portion. The electrostatic chuck can be used in semiconductor processing equipment.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an electrostatic chuck, a processing chamber and a semiconductor processing device. Background Art

[0002] Electrostatic chucks are commonly used to fix wafers during the manufacturing process of semiconductor devices. For example, electrostatic chucks can be used in plasma etching processes or plasma deposition processes to maintain the position of the processed wafer and the support surface using electrical electrostatic attraction.

[0003] However, in the above process, during the plasma treatment, the wafer fixed on the electrostatic chuck will be in contact with the high temperature plasma, so that the temperature of the wafer increases. The increase in wafer temperature may cause changes in the wafer etching rate and morphology, affecting the wafer yield. Summary of the invention

[0004] The object of the present invention is to provide an electrostatic chuck, a processing chamber and a semiconductor processing device for ensuring the yield of a wafer in a plasma etching or deposition process.

[0005] In order to achieve the above object, the present invention provides an electrostatic chuck, which is used to fix a wafer, and the electrostatic chuck comprises:

[0006] An electrostatic chuck body, wherein the electrostatic chuck body has a receiving cavity;

[0007] An electrostatic adsorption part, which is located on the surface of the electrostatic chuck body close to the wafer and is used to fix the wafer;

[0008] A cooling laser is arranged in the accommodating cavity and is used for emitting a cooling laser to the electrostatic adsorption part so as to cool the wafer fixed on the electrostatic adsorption part.

[0009] Compared with the prior art, in the electrostatic chuck provided by the present invention, an electrostatic adsorption part is provided on the electrostatic chuck body, and the electrostatic adsorption part can tightly adsorb the wafer on the electrostatic adsorption part through electrostatic adsorption force. In addition, a cooling laser is provided in the accommodating cavity between the electrostatic chuck body and the electrostatic adsorption part. In the above case, during the process of processing the wafer by plasma etching or deposition process, the cooling laser can emit a cooling laser to the electrostatic adsorption part. The photons in the cooling laser can collide with the atoms possessed by the electrostatic adsorption part, so that the movement speed of the atoms in the electrostatic adsorption part is reduced, thereby reducing the temperature of the electrostatic adsorption part. At this time, the electrostatic adsorption part can absorb the heat in the wafer by heat conduction, so that the temperature of the wafer is still maintained near the electrode setting temperature during a long plasma reaction, so as to ensure the yield of the wafer.

[0010] The present invention also provides a processing chamber, which includes the electrostatic chuck provided by the above technical solution.

[0011] Compared with the prior art, the beneficial effects of the processing chamber provided by the present invention are the same as the beneficial effects of the electrostatic chuck provided by the above technical solution, which will not be described in detail here.

[0012] The present invention also provides a semiconductor processing device, which includes a processing chamber provided by the above technical solution.

[0013] Compared with the prior art, the beneficial effects of the semiconductor processing equipment provided by the present invention are the same as the beneficial effects of the electrostatic chuck provided by the above technical solution, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0015] Figure 1 A longitudinal cross-sectional view of the structure of an electrostatic chuck provided by an embodiment of the present invention;

[0016] Figure 2 A distribution diagram of the cooling laser provided in an embodiment of the present invention on the bottom surface of the accommodating cavity.

[0017] Reference numerals:

[0018] 1 is an electrostatic chuck body, 11 is a receiving cavity, 2 is an electrostatic adsorption portion, 21 is an electrostatic plate, 22 is a fixing plate, 3 is a cooling laser, 31 is a first cooling laser, and 32 is a second cooling laser. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0020] Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0021] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element. In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0023] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] An electrostatic chuck is a device that can hold a wafer in place during the manufacturing process of a semiconductor device. For example, an electrostatic chuck can be used in a plasma etching process or a plasma deposition process to maintain the position of the wafer being processed and the support surface using electrical electrostatic attraction.

[0025] However, in the process of etching the wafer using a plasma etching process, or depositing the corresponding film layer on the wafer using a plasma deposition process, during the plasma treatment, the wafer fixed on the electrostatic chuck is usually heated by the high-temperature plasma in contact with it, causing the temperature of the wafer to change, making it impossible to maintain a constant temperature for the wafer to react to the plasma during the etching or deposition process, which may cause changes in the wafer etching rate and morphology, and ultimately affect the wafer yield.

[0026] In order to solve the above technical problems, an embodiment of the present invention provides an electrostatic chuck, a processing chamber and a semiconductor processing device. Among them, in the electrostatic chuck provided by the embodiment of the present invention, a cooling laser is arranged in the accommodating cavity between the electrostatic chuck body and the electrostatic adsorption part. The cooling laser can maintain a constant temperature of the wafer to plasma reaction during the plasma etching or deposition process, thereby improving the yield of the wafer.

[0027] See also Figure 1 and Figure 2 An embodiment of the present invention provides an electrostatic chuck, which includes: an electrostatic chuck body 1, an electrostatic adsorption part 2 and a cooling laser 3.

[0028] See also Figure 1 The electrostatic chuck body 1 has a receiving cavity 11. The electrostatic adsorption portion 2 is located on the surface of the electrostatic chuck body 1 close to the wafer and is used to fix the wafer.

[0029] Specifically, in order to better fix the wafer, the structure of the electrostatic chuck body and the electrostatic adsorption part can be set according to the shape and specifications of the wafer. For example, the electrostatic chuck body and the electrostatic adsorption part can be circular or disc-shaped. In addition, a receiving cavity can be provided on one side of the electrostatic chuck body close to the electrostatic adsorption part to accommodate the cooling laser. The shape of the radial cross-section of the receiving cavity can be circular or other shapes. The electrostatic adsorption part covers the top of the receiving cavity.

[0030] See also Figure 1 For the above-mentioned electrostatic adsorption part 2, the electrostatic adsorption part 2 may include an electrostatic plate 21, and a fixed plate 22 arranged on the electrostatic plate 21. Among them, the electrostatic plate 21 can be tightly connected with the fixed plate 22 by means of bolts and nuts. In the actual application process, when power such as DC voltage is applied to the electrostatic plate 21, an electrostatic force can be generated between the electrostatic plate 21 and the wafer. The wafer can be adsorbed on the upper surface of the fixed plate 22 located on the electrostatic plate 21 by electrostatic force. Among them, the material of the electrostatic plate 21 may include a material with good electrical conductivity.

[0031] See also Figure 1For the fixed plate 22, the upper surface of the fixed plate 22 can be a flat horizontal plane so that the wafer can be strongly attached to the upper surface of the fixed plate 22. Since the fixed plate 22 needs to withstand the high-temperature plasma generated during the plasma etching or deposition process, the material of the fixed plate 22 can include a material with less thermal deformation. In addition, the material of the fixed plate 22 can be a non-conductor material to protect the wafer from the high voltage applied to the electrostatic plate 21. In addition, the thickness of the fixed plate 22 will affect the electrostatic force applied to the wafer by the electrostatic plate 21 under the action of high voltage. Specifically, when other factors are the same, the thicker the thickness of the fixed plate 22, the smaller the electrostatic force applied to the wafer. Conversely, the thinner the thickness of the fixed plate 22, the greater the electrostatic force applied to the wafer, so the thickness of the fixed plate 22 can be set according to the requirements for wafer fixation in actual application scenarios.

[0032] See also Figure 1 and Figure 2 The cooling laser 3 is disposed in the accommodating cavity 11 and is used to emit cooling laser to the electrostatic adsorption part 2 to cool the wafer fixed on the electrostatic adsorption part 2 .

[0033] Specifically, the cooling laser can be fixedly connected to the bottom surface of the accommodating cavity by bolts, bonding, etc., or fixedly connected to the side wall of the accommodating cavity. The specific setting position of the cooling laser in the accommodating cavity and the number of cooling lasers set in the accommodating cavity can be set according to the actual application scenario, as long as the wafer can be cooled.

[0034] In one example, the number of cooling lasers can be one or more. When the number of cooling lasers is one, the cooling laser can be arranged at the center of the bottom surface of the accommodating cavity. Figure 1 and Figure 2 When there are multiple cooling lasers 3, the multiple cooling lasers 3 can be evenly arranged on the bottom surface of the accommodating cavity 11. In addition, when there are multiple cooling lasers 3, there can be a gap between two adjacent cooling lasers 3. Moreover, the gaps between two different adjacent cooling lasers 3 can be equal or unequal.

[0035] For example, see Figure 1 and Figure 2 When there are multiple cooling lasers 3, the multiple cooling lasers 3 may include a first cooling laser 31 located at the bottom center of the accommodating cavity 11, and at least two groups of cooling lasers 3 distributed in concentric circles with the bottom center of the accommodating cavity 11 as the center. Each group of cooling lasers 3 may include at least two second cooling lasers 32.

[0036] Specifically, the intervals between two adjacent second cooling lasers in the same group may be equal or unequal. When the multiple lasers include at least three groups of cooling lasers distributed in concentric circles, the intervals between each two adjacent groups of cooling lasers may be equal or unequal. When the above intervals are equal, the distribution of the multiple cooling lasers on the bottom surface of the accommodating cavity has good uniformity, and the temperature of each area of ​​the electrostatic adsorption part can be uniformly reduced during the plasma etching or deposition process, thereby keeping the temperature of each area of ​​the electrostatic adsorption part consistent, so that each area on the back of the wafer tightly adsorbed on the electrostatic adsorption part can be uniformly cooled.

[0037] The number of groups of cooling lasers distributed in concentric circles with the bottom center of the accommodating cavity as the center can be set according to the specifications of the cooling lasers and the shape and specifications of the wafer, and is not specifically limited here. In addition, the number of second cooling lasers included in each group of cooling lasers can be the same or different. For example, see Figure 2 , along the direction from the center to the edge of the bottom surface of the accommodating cavity 11, the number of second cooling lasers 32 included in each group of cooling lasers gradually increases. The number of second cooling lasers 32 included in each group of cooling lasers can be set according to the specifications of the concentric circles and the specifications of the second cooling lasers 32, which are not specifically limited here.

[0038] For example: See Figure 2 When the number of cooling lasers 3 is multiple, the multiple cooling lasers 3 may include a first cooling laser 31 located at the center of the cavity bottom, and a first group of cooling lasers and a second group of cooling lasers distributed in concentric circles with the center of the cavity bottom as the center. The first group of cooling lasers is located between the first cooling laser 31 and the second group of cooling lasers. The spacing between the first cooling laser 31 and the first group of cooling lasers is equal to the spacing between the first group of cooling lasers and the second group of cooling lasers. The first group of cooling lasers includes 4 second cooling lasers 32. The second group of cooling lasers includes 8 second cooling lasers 32.

[0039] In addition, see Figure 1 When there are multiple cooling lasers 3, the tops of the multiple cooling lasers 3 can be flush. At this time, the distance between the light-emitting portion of each cooling laser 3 and the bottom of the electrostatic adsorption portion 2 is equal, further ensuring that under the cooling effect of the multiple cooling lasers 3, the temperature of each area of ​​the electrostatic adsorption portion 2 is uniformly reduced.

[0040] As for the type of cooling laser, the cooling laser may be any cooling laser that can reduce the temperature of the electrostatic adsorption portion and cool the wafer. For example, the cooling laser may be an ultraviolet cooling laser.

[0041] Specifically, the atoms of an object are always moving irregularly, which is actually the thermal motion of the object's temperature. Specifically, the more intense the atomic motion, the higher the temperature of the object. Conversely, the lower the temperature of the object. Therefore, as long as the speed of atomic motion is reduced, the temperature of the object can be reduced. Based on this, the principle of cooling laser refrigeration is to use a large number of photons to hinder the movement of atoms, slowing them down, thereby reducing the temperature of the object. Correspondingly, the material of the electrostatic adsorption part can be a laser-permeable material. At this time, the cooling laser emitted by the cooling laser can penetrate the electrostatic adsorption part. In addition, the photons in the cooling laser can collide with the atoms in the electrostatic adsorption part in the process of penetrating the electrostatic adsorption part, slowing them down, thereby reducing the temperature of the electrostatic adsorption part, and then cooling the wafer. Among them, the specific type of the above-mentioned laser-permeable material can be selected according to the functions of the various structures included in the electrostatic adsorption part.

[0042] For example, as described above, when the electrostatic adsorption portion includes an electrostatic plate and a fixed plate located on the electrostatic plate, the electrostatic plate and the fixed plate can be made of materials that are laser-transmissible. Alternatively, the electrostatic plate can be made of a laser-transmissible material with good electrical conductivity, while the fixed plate can be made of a material with good thermal conductivity and insulation.

[0043] For example, the material of the electrostatic plate can be iron, copper, silver, etc. The material of the fixed plate can be quartz or ceramic, etc.

[0044] It can be seen from the above that when the wafer is processed by plasma etching or deposition process, in the electrostatic chuck provided by the embodiment of the present invention, the cooling laser can emit cooling laser to the electrostatic adsorption part. The photons in the cooling laser can collide with the atoms in the electrostatic adsorption part, so that the movement speed of the atoms in the electrostatic adsorption part is reduced, thereby reducing the temperature of the electrostatic adsorption part. At this time, the electrostatic adsorption part can absorb the heat in the wafer by heat conduction, so that the temperature of the wafer is still maintained near the electrode setting temperature during a long plasma reaction, thereby achieving rapid cooling of the wafer and ensuring the yield of the wafer.

[0045] An embodiment of the present invention further provides a processing chamber, which includes the electrostatic chuck provided by the above embodiment.

[0046] Specifically, the processing chamber may be a chamber capable of performing plasma etching or a chamber capable of performing plasma deposition.

[0047] Compared with the prior art, the beneficial effects of the processing chamber provided by the embodiment of the present invention are the same as the beneficial effects of the electrostatic chuck provided by the above embodiment, and are not described in detail here.

[0048] An embodiment of the present invention further provides a semiconductor processing device, which includes the processing chamber provided by the above embodiment.

[0049] Specifically, the semiconductor processing equipment may be any equipment that uses plasma to etch wafers, such as reactive ion etching equipment and inductively coupled plasma etching equipment. Alternatively, the semiconductor processing equipment may also be any equipment that uses plasma to deposit a film layer on a wafer, such as plasma chemical vapor deposition equipment and plasma-assisted physical vapor deposition equipment.

[0050] Compared with the prior art, the beneficial effects of the semiconductor processing equipment provided by the embodiment of the present invention are the same as the beneficial effects of the electrostatic chuck provided by the above embodiment, which will not be described in detail here.

[0051] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, a person skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. An electrostatic chuck, characterized in that: For fixing the wafer, the electrostatic chuck comprises: An electrostatic chuck body, wherein the electrostatic chuck body has a receiving cavity; An electrostatic adsorption part, which is located on the surface of the electrostatic chuck body close to the wafer and is used to fix the wafer, and the material of the electrostatic adsorption part is a material that can be penetrated by laser; A cooling laser is disposed in the accommodating cavity and is used to emit a cooling laser to the electrostatic adsorption portion to cool the wafer fixed on the electrostatic adsorption portion.

2. The electrostatic chuck according to claim 1, characterized in that: The cooling laser is an ultraviolet cooling laser.

3. The electrostatic chuck according to any one of claims 1 to 2, characterized in that: The number of the cooling lasers is one or more; When the number of the cooling laser is one, the cooling laser is arranged at the center of the bottom surface of the accommodating cavity; When there are multiple cooling lasers, the multiple cooling lasers are evenly arranged on the bottom surface of the accommodating cavity.

4. The electrostatic chuck according to claim 3, characterized in that: When there are multiple cooling lasers, there is a gap between two adjacent cooling lasers, and the tops of the multiple cooling lasers are flush.

5. The electrostatic chuck according to claim 3, characterized in that: When there are multiple cooling lasers, the multiple cooling lasers include a first cooling laser located at the center of the bottom surface of the accommodating cavity, and at least two groups of cooling lasers distributed in concentric circles with the center of the bottom surface of the accommodating cavity as the center, and each group of cooling lasers includes at least two second cooling lasers.

6. The electrostatic chuck according to claim 5, characterized in that: The intervals between two adjacent second cooling lasers in the same group are equal.

7. The electrostatic chuck according to claim 5, characterized in that: Along the direction from the center to the edge of the bottom surface of the accommodating cavity, the number of the second cooling lasers included in each group of the cooling lasers gradually increases.

8. A processing chamber, characterized in that: The invention comprises the electrostatic chuck as claimed in any one of claims 1 to 7.

9. A semiconductor processing device, characterized in that: Comprising the processing chamber of claim 8.

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