Vacuum wafer chuck with solid diamond pin

Abstract

To provide a vacuum wafer chuck with a solid diamond pin.SOLUTION: A VCSEL device may include multiple layers forming a protection diode outside of a region of a lithographic aperture, and the protection diode has a surface area greater than a surface area of the lithographic aperture.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This disclosure relates generally to a vacuum wafer chuck having solid diamond pins. [Background technology]

[0002]

[0002] Aspects of the present disclosure relate to a vacuum wafer chuck having a solid diamond pin. Various problems may exist in conventional solutions for a vacuum wafer chuck having a solid diamond pin. In this regard, conventional systems and methods for a vacuum wafer chuck having a solid diamond pin may be costly, cumbersome, and / or inefficient.

[0003]

[0003] Limitations and drawbacks of conventional systems and methods will become apparent to those skilled in the art upon comparison of such approaches with certain aspects of the present methods and systems described in the remainder of this disclosure with reference to the drawings. Summary of the Invention

[0004] A vacuum wafer chuck having solid diamond pins is shown and / or described in connection with at least one of the drawings and fully set forth in the claims.

[0005] These and other advantages, aspects, and novel features of the present disclosure, as well as details of illustrated embodiments thereof, will be more fully understood from the following description and drawings.

[0005]

[0006] The various features and advantages of the present disclosure may be more readily understood by reference to the following detailed description in conjunction with the accompanying drawings, in which like reference numerals indicate similar structural elements and in which: [Brief description of the drawings]

[0006] [Figure 1]

[0007] FIG. 1 is a block diagram illustrating a reaction bonded silicon carbide body according to some embodiments of the present disclosure. [Diagram 2]

[0008] FIG. 2 is a block diagram further illustrating the reaction bonded silicon carbide body 100 of FIG. [Figure 3a]

[0009] FIG. 3 a is a cross-sectional view of a reaction-bonded ceramic material 20 . [Figure 3b] FIG. 3 b is a cross-sectional view of reaction bonded ceramic material 20 . [Figure 3c] FIG. 3 c is a cross-sectional view of reaction bonded ceramic material 20 . [Figure 3d] FIG. 3 d is a cross-sectional view of reaction-bonded ceramic material 20 . [Figure 4a]

[0010] FIG. 4a is a plan view of an example multi-component block. [Figure 4b]

[0011] FIG. 4b shows an exemplary detail of FIG. 4a. [Figure 4c] FIG. 4c shows an exemplary detail of FIG. 4a. [Diagram 5]

[0012] FIG. 1 illustrates an exemplary reaction bonded silicon carbide body 100 using a single diamond grain 122 in the discrete elements 120 prior to machining. [Figure 6]

[0013] 1A-1D are cross-sectional and top views of a reaction bonded silicon carbide body after machining. [Figure 7]

[0014] 1 is a flow chart illustrating a method according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007]

[0015] The following description provides various examples of semiconductor devices and methods of manufacturing semiconductor devices. Such examples are not limiting, and the appended claims should not be limited to the specific examples disclosed. In the following description, the terms "example" and "for example" are not limiting.

[0008]

[0016] The figures show common configuration manners, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the present disclosure. In addition, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of the examples described in the present disclosure. The same reference symbols in different figures refer to the same elements.

[0009]

[0017] The term "or" means any one or more of the items in the list joined by "or." As an example, "x or y" means any element of the three element set {(x), (y), (x,y)}. As another example, "x, y, or z" means any element of the seven element set {(x), (y), (z), (x,y), (x,z), (y,z), (x,y,z)}.

[0010]

[0018] The terms "comprises," "comprising," "includes," and / or "including" are "open-ended" terms and specify the presence of stated features and do not exclude the presence or addition of one or more other features.

[0011]

[0019] Terms such as "first", "second" and the like may be used herein to describe various elements, and these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. Thus, for example, a first element described in this disclosure may be called a second element without departing from the teachings of this disclosure.

[0012]

[0020] Unless otherwise specified, the term "coupled" may be used to describe two elements that are in direct contact with each other or two elements that are indirectly connected by one or more other elements. For example, if element A is coupled to element B, element A may be in direct contact with element B or indirectly connected to element B by an intervening element C. Similarly, the terms "over" or "on" may be used to describe two elements that are in direct contact with each other or two elements that are indirectly connected by one or more other elements.

[0013]

[0021] Referring now to FIG. 1 , a block diagram illustrating a reaction bonded silicon carbide body 100 according to some embodiments of the present disclosure is shown. In some embodiments, the reaction bonded silicon carbide body 100 can include a body portion 110. The reaction bonded silicon carbide body 100 can also include one or more discrete elements 120 of a dimension located at least partially within the body portion 110. The body portion 110 can be free of diamond and include reaction bonded silicon carbide 112 and elemental silicon 114. The one or more discrete elements 120 can also include a single diamond grain 122 of that dimension. The reaction bonded silicon carbide 112 can surround the diamond grain 122 and elemental silicon 114.

[0014]

[0022] In some embodiments, body portion 110 may be configured for use in a vacuum wafer chuck. In some embodiments, discrete elements 120 may be configured to provide high heat flux beneath the die without reducing the machinability of body portion 110. In some embodiments, discrete elements 120 may be configured to provide localized diamond reinforcement at the wear surface without reducing the machinability of body portion 110.

[0015]

[0023] 2 is a block diagram further illustrating the reaction bonded silicon carbide body 100 of FIG. 1 according to some embodiments of the present disclosure. In some embodiments, the one or more discrete elements 120 can include a pin 216 for supporting, for example, a semiconductor wafer. In some embodiments, the pin 216 can include a first portion 217 located within the body portion 110 and a second portion 218 that protrudes above the body portion 110 and the first portion 217. In some embodiments, the first portion 217 of the pin 216 can include a first diameter 220. The second portion 218 can include a second diameter 222. The first diameter 220 can be smaller than the second diameter 222, and the second (or first) diameter 222 can be substantially equal in dimension.

[0016]

[0024] 3a-3d are cross-sectional views of a reaction-bonded ceramic material 20 including ceramic particles 22, reaction-formed silicon carbide (SiC) particles 24, and residual elemental silicon (Si) 26. The ceramic particles 22 may include SiC or boron carbide (B4C). The ceramic material 20 may be produced by performing a reactive infiltration process on a preform 30 (FIG. 3b) including ceramic particles 22 and elemental carbon 32. During the infiltration process, molten Si can infiltrate the preform 30 to form reaction-formed SiC particles 24. That is, the molten Si can react with the carbon 32 to form additional SiC. Despite the infiltration of Si into the preform 30, the process may result in only a slight increase in volume (the increase in the volume of the ceramic material 20 compared to the volume of the preform 30), which may be, for example, less than 1 percent. The ceramic material 20 shown in FIG. 3a does not contain diamond. FIG. 3c is a cross-sectional view of a reaction-bonded ceramic material 40 including reaction-formed SiC particles 24, residual elemental Si 26, diamond particles 42, reaction-formed SiC coatings 44 on and surrounding the diamond particles 42, and, optionally, ceramic particles 22. The ceramic particles 22 may include SiC or B4C, as appropriate. The ceramic material 40 may be produced by performing a reactive infiltration process on a preform 50 (FIG. 3d), which may include a powder and includes optional ceramic particles 22, elemental carbon 32, and diamond particles 42. During the reactive infiltration process, molten Si infiltrates the preform 50 to form reaction-formed SiC particles 24 and reaction-formed SiC coatings 44. If desired, the coating 44 may completely surround the diamond particles 42 such that in the cross-sectional view of FIG. 3c, the coating 44 appears as a halo surrounding the particles 42. During the reactive infiltration process, the molten Si reacts with the carbon 32 to form additional SiC, and the molten Si also reacts with the surfaces of the diamond particles 42 to produce a reactively formed SiC coating 44 .Despite the infiltration of molten Si into the preform 50, this process may result in only a small increase in volume (the increase in the volume of the ceramic material 40 compared to the volume of the preform 50) that may be less than one percent.

[0017]

[0025] The material 40 shown in FIG. 3c, which includes a composite of reaction-bonded SiC 24, 44, diamond particles 42 (SiSiC-diamond), may be considered for many high-end applications, since the material 40 may have low thermal expansion, high thermal conductivity, high hardness, high wear resistance, high stiffness, and low coefficient of friction. However, the diamond particles 42 may make the material 40 extremely difficult to machine (cut, grind, and / or shape). Thus, according to the present disclosure, a reaction-bonded SiC body may be provided with discrete reinforcing elements, which include diamond particles 42, while the main body, e.g., the body portion 110, does not contain diamond. According to the present disclosure, the diamond-containing material 40 shown in FIG. 3c may be provided only as required to provide the desired performance. The remainder of the body may be formed of the material 20 shown in FIG. 3a, which contains reaction-bonded SiC 24 but does not contain diamond, and is well suited for cost-effective machining.

[0018]

[0026] Diamond has many desirable properties for a variety of useful applications. Such properties include extremely high hardness for wear resistance, very low coefficient of friction for sliding applications, very high stiffness (Young's modulus) for structural applications, and very high thermal stability (high thermal conductivity and low coefficient of thermal expansion (CTE)). According to various embodiments of the present disclosure, desirable diamond particles may be single crystal and / or polycrystalline. Often, polycrystalline diamond particles may exhibit more uniform properties, such as hardness, in different physical directions / faces of the crystal grain.

[0019]

[0027] FIG. 4a is a plan view of an example of a multi-component block. The illustrated block includes a body 110 (an example of a body portion 110) formed of a SiC-containing material 20 shown in FIG. 3a, and spaced apart discrete features 104 formed of a diamond-containing material shown in FIG. 3c. The features 104 may be located within corresponding trenches 106 (an example of a surface feature, FIG. 4b) laser machined into a top surface 108 of the SiC-containing body 102. In the illustrated example, each feature 104 may have a width W in the range of 0.5 mm to 3.0 mm, preferably about 1.2 mm, and a depth D in the range of 100 μm to 600 μm, preferably about 300 μm, and the trenches 106 may be at least partially filled with an appropriate amount of diamond powder, such as nominally 65 μm. However, the disclosure should not be limited to the details of the examples described herein.

[0020]

[0028] Then, after the trenches 106 are filled with diamond powder, molten Si is simultaneously infiltrated into the body 110 and the trenches 106 to produce the material 20 shown in Figure 3a with reaction-bonded SiC 24 (Figure 4c) in the body 110 and to produce the diamond-containing material 40 in (and only in) the trenches 106. As a result, the multi-component block can provide the high performance properties associated with diamond-containing material 40 using the discrete features 104 only where desired, while the remainder of the block 100 (i.e., the body 110) contains reaction-formed SiC but no diamond and can therefore be more easily machinable.

[0021]

[0029] In other words, the illustrated multi-component block may have hard, thermally conductive diamond reinforced composite material 40 where (and only where) necessary, and reaction-bonded SiC 20 (without diamond) in other areas for ease of machining. The body 110 and features 104 shown in Figure 4a represent one example of a wide variety of applications where localized diamond-containing reinforcement may be of value, such as when a very hard, low friction material is desired only in specific locations of a component where wear would otherwise occur, or to provide a thermally stable, very high thermal conductivity path only where heat sinking and / or heat spreading is required, or to provide very stiff (i.e. high Young's modulus) areas only where low mechanical deflection is desired.

[0022]

[0030] In the illustrated example, the reaction occurring within trench 106 containing Si+diamond is different from the reaction occurring simultaneously elsewhere within body 110 containing Si+carbon but no diamond. As a result, the residual elemental Si content within the diamond-reinforced region (within trench 106) is lower than that in the remainder of the block. For example, the residual elemental Si within the diamond-reinforced region within trench 106 may be, for example, about 6.8%, while the residual Si within the SiSiC (and no diamond) region may be, for example, about 23.2%.

[0023]

[0031] Although low residual Si content in diamond reinforced regions may result in improved properties (hardness, stiffness, inertness, etc.), the combination of diamond particles and low elemental Si content may make machining particularly difficult, and as a result, it may be particularly advantageous to provide diamond-containing features 104 only where they are needed. However, avoiding difficult machining is only one of many reasons why it may be advantageous to localize diamond-containing features. Another advantage of providing diamond reinforcement only where it can be effectively used is cost reduction. In other words, it is advantageous to use expensive diamond powder only where it is needed.

[0024]

[0032] 5 shows an exemplary reaction bonded silicon carbide body 100 prior to machining, using a single diamond grain 122 in the discrete elements 120. The reaction bonded silicon carbide body 100 is shown including a body portion 110, which includes a single diamond grain 122, reaction bonded silicon carbide 112, and elemental silicon 114. The body portion 110 does not contain any diamond other than the diamond grain 122.

[0025]

[0033] According to various embodiments of the present disclosure, it may be desirable to create a feature, for example feature 104, that does not include diamond powder, but instead includes a single diamond particle 122. Again, body portion 110 does not include diamond other than particle 122. Diamond particle 122 may be of significantly larger dimensions than diamond particles used in powder form such as those shown in Figures 4a-4c. Diamond particle 122 may have dimensions of, for example, 600 μm. In this manner, diamond particle 122 may be embedded in body portion 110.

[0026]

[0034] According to various embodiments of the present disclosure, it may be desirable to create features from diamond grains 122. For example, as shown in Figure 6, it may be desirable to form a round pin having a solid diamond surface from diamond grains 122 along dashed lines, which may ultimately be raised.

[0027]

[0035] FIG. 6 shows a cross-sectional view and a top view of a reaction bonded silicon carbide body 100 after machining. The reaction bonded silicon carbide body 100, body portion 110 is shown. Discrete elements 120 including pins 216 are shown. The pins 216 may be formed from a single diamond grain 122 by machining. The pins 216 include a first portion 217 located within the body portion 110 and a second portion 218 that may protrude from the surface of the body portion 110. The pins 216 may include a top surface 212. The pins 216 may be, for example, frustoconical in shape having a first base diameter 220 and a second, smaller diameter 222. According to various embodiments of the present disclosure, the pins 216 may be any suitable shape, for example, a triangular, square, or pentagonal pyramid. In some embodiments, the frustum may approach or even be substantially cylindrical. In some embodiments, the shape of the pin 216 may include multiple stacked frustums, or the shape may be replicated by any number of stacked frustums. The diameter of the pin 216, often due to its slightly conical shape, may be a nominal dimension that may be considered to be equal to, for example, the first diameter 220, the second diameter 222, or somewhere between the first diameter 220 and the second diameter 222.

[0028]

[0036] A structure such as the pin 216 as shown in FIG. 6 may be machined from a single diamond grain 122 embedded in a body portion 110 (FIG. 5) that includes, for example, reaction-bonded silicon carbide 112 and elemental silicon 114. The machining may include simple surface grinding to create a common top surface that can later create the flat top surface 212 of the pin 216. More of the body portion 110 may then be removed by machining to form the pins 216 and raise them above the top surface of the body portion 110. A suitable machining may be laser cutting. Thus, the pins 216 may be discrete elements of a certain dimension (diameter) that may be partially located within the body portion 110. The diameter of the diamond-containing pin 216 may be, for example, in the range of 200 μm to 800 μm, preferably about 400 μm. Similarly, the height of the pins 216 may be in the range of 200 μm to 800 μm, preferably about 400 μm, but these are only examples of how the present disclosure may be implemented. The disclosure should not be limited to the details of the examples set forth herein.

[0029]

[0037] FIG. 7 is a flow chart illustrating a method according to some embodiments of the present disclosure. In some embodiments, at 310, the method can include embedding a single diamond grain 122 of pre-cut dimensions in the body portion 110 (see also FIG. 5). At 320, the method can include cutting one or more discrete elements 120 of a dimension, each of which is smaller than the pre-cut dimension, each discrete element 120 located at least partially within the body portion 110. The body portion 110 can include reaction-bonded silicon carbide 112, elemental silicon 114, and no diamond on the outside of the discrete elements, e.g., grains 122. Each discrete element 120, e.g., pin 216, can include a single diamond grain 122 of post-cut dimensions.

[0030]

[0038] According to various embodiments of the present disclosure, the method may include cutting one or more discrete elements 120 of a dimension, each of which is smaller than the dimension before cutting, each discrete element 120 located at least partially within the body portion 110, and each discrete element 120 comprising a single diamond grain 122 of that dimension.

[0031]

[0039] In some embodiments, the method can include configuring the body portion 110 for use in a vacuum wafer chuck. In some embodiments, the method can include configuring the discrete elements 120, e.g., pins 216, to provide high heat flux beneath the die without reducing the machinability of the body portion 110. In some embodiments, the method can include configuring the discrete elements 120 to provide localized diamond reinforcement at the wear surface (e.g., top surface 212) without reducing the machinability of the body portion 110.

[0032]

[0040] In some embodiments, the method can include cutting the discrete elements 120 to form pins 216 for supporting a semiconductor wafer. In some embodiments, the method can include forming the pins 216 to include a first portion 217 located within the body portion 110 and to protrude above the body portion 110. As in FIG. 6, the pins can include a first portion 217 having a first diameter 220 and a second portion 218 having a second diameter 222. In some embodiments, for example, the first diameter can be greater than or equal to the second diameter and the second diameter can be substantially equal to that dimension.

[0033]

[0041] In some embodiments, the method can include forming the pins such that they can be separated from one another to prevent bimetallic strip stress.

[0042] Although the present disclosure includes reference to several examples, it will be understood by those skilled in the art that various modifications may be made and equivalents may be substituted without departing from the scope of the present disclosure. Additionally, changes may be made to the disclosed examples without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the disclosed examples, but is intended to include all examples that fall within the scope of the appended claims. [Explanation of symbols]

[0034] 20 Reaction-bonded ceramic materials, ceramic materials, materials, reaction-bonded SiC 22 Ceramic particles 24 Reaction-formed silicon carbide (SiC) particles, reaction-formed SiC particles, reaction-bonded SiC 26 Residual element silicon (Si) 30 Preform 32 Element Carbon, Carbon 40 Reaction-bonded ceramic materials, ceramic materials, materials, diamond-containing materials 42 Diamond particles, particles 44 Reaction-formed SiC coatings, coatings, reaction-bonded SiC 50 Preforms 100 Reaction bonded silicon carbide bodies 102 SiC-containing body 104 Spaced discrete features, features 106 Trench 108 Top surface 110 Main body part, main body 112 Reaction-bonded silicon carbide, reaction-bonded silicon carbide 114 Elemental Silicon 120 discrete elements 122 Single diamond particle, diamond particle, particle 212 Top surface 216 pin 217 First Part 218 Second Part 220 first diameter, first base diameter 222 second diameter, second smaller diameter

Claims

1. 1. A reaction bonded silicon carbide body comprising: a body portion comprising reaction bonded silicon carbide and elemental silicon, the body portion being free of diamond; one or more discrete elements of a dimension located at least partially within said body portion, each of said discrete elements being a reaction-bonded silicon carbide coating surrounding said diamond particle; and elemental silicon. one or more discrete elements; 1. A reaction bonded silicon carbide body comprising:

2. 10. The reaction bonded silicon carbide body of claim 1 , wherein the body portion is configured for use in a vacuum wafer chuck.

3. 10. The reaction bonded silicon carbide body of claim 1 , wherein the discrete elements include pins for supporting a semiconductor wafer.

4. 4. The reaction bonded silicon carbide body of claim 3, wherein the pin includes a first portion located within the body portion and the pin includes a second portion that protrudes above the body portion and the first portion.

5. 5. The reaction bonded silicon carbide body of claim 4, wherein the first portion of the pin has a first diameter and the second portion of the pin has a second diameter, the first diameter being greater than the second diameter and the second diameter being substantially equal to the dimension.

6. 4. The reaction bonded silicon carbide body of claim 3, wherein the pins are separated from one another to prevent bimetallic strip stresses.

7. 10. The reaction bonded silicon carbide body of claim 1 , wherein the discrete elements are configured to provide high heat flux beneath a die without reducing machinability of the body portion.

8. 10. The reaction bonded silicon carbide body of claim 1 , wherein the discrete elements are configured to provide localized diamond reinforcement at a wear surface without reducing machinability of the body portion.

9. 10. The reaction bonded silicon carbide body of claim 1, wherein the single diamond grains may comprise single crystals or polycrystals.

10. 1. A method of making a reaction bonded silicon carbide body, comprising: embedding a single diamond particle of pre-cutting dimensions in a body portion, said body portion comprising reaction-bonded silicon carbide and elemental silicon and no diamond; cutting one or more discrete elements of a dimension, each of the dimensions being smaller than the dimension before cutting, each of the discrete elements being at least partially located within the body portion, each of the discrete elements comprising a single diamond grain of the dimension, a reaction-bonded silicon carbide coating surrounding the diamond grain, and elemental silicon; The method includes:

11. 11. The method of claim 10, comprising configuring the body portion for use in a vacuum wafer chuck.

12. 11. The method of claim 10, comprising cutting the discrete elements to form pins for supporting a semiconductor wafer.

13. 13. The method of claim 12, comprising forming the pin to include a first portion located within the body portion and a second portion raised above the body portion and the first portion.

14. 14. The method of claim 13, comprising forming the first portion of the pin to have a first diameter and forming the second portion of the pin to have a second diameter, the first diameter being greater than the second diameter and the second diameter being substantially equal to the dimension.

15. 13. The method of claim 12 including forming the pins to be separated from one another to prevent bimetallic strip stresses.

16. 11. The method of claim 10, comprising configuring the discrete elements to provide high heat flux beneath a die without reducing machinability of the body portion.

17. 11. The method of claim 10, comprising configuring the discrete elements to provide localized diamond reinforcement at a wear surface without reducing machinability of the body portion.

18. 11. A method according to claim 10, comprising the step of selecting the single diamond grain from a monocrystalline grain or a polycrystalline grain.

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