Semiconductor back deposition base

Abstract

The invention discloses a semiconductor back deposition base which comprises a panel, a middle base plate and a bottom base plate, the panel, the middle base plate and the bottom base plate are sequentially arranged in a stacked mode, an air inlet cavity is jointly defined by the panel and the middle base plate, and a plurality of spraying holes communicated with the air inlet cavity are formed in the panel; the bottom substrate and the middle substrate are fixedly connected through vacuum brazing welding. According to the semiconductor back deposition base disclosed by the invention, the bottom substrate and the middle substrate of the base as well as the heating wire and the middle substrate are welded and fixed by adopting vacuum brazing, so that the problem of deformation caused by non-uniform stress among parts due to repeated heating in a long-term use process of a spraying disc is solved; other parts are welded and fixed through electron beam welding, and the problem that micro-particles are prone to being generated on the spraying disc is solved.

Description

Technical Field

[0001] The invention relates to the technical field of a spray plate mechanism in a semiconductor device, and in particular to a semiconductor backside deposition base. Background Art

[0002] In the prior art, there is a process that requires deposition of a thin film on the back of a wafer, wherein the key mechanism is a base with a spray and heating structure. In the prior art, the base is generally fixedly connected by rotating friction welding or EB (electron beam welding) of three-series aluminum.

[0003] However, in the above-mentioned base mechanism design, the base needs to be repeatedly heated and cooled for a long time. The existing design uses a fixed connection method of rotary friction welding or electron beam welding for all components, which will cause uneven thermal stress generated by the heat energy transferred by the heating wire, further causing deformation of the base. The deformed base will affect the quality of thin film deposition. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a semiconductor backside deposition base to solve the technical problem that the existing heating spray plate is easily deformed after long-term use.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] An embodiment of the present invention provides a semiconductor back side deposition base, which includes: a panel, an intermediate substrate and a bottom substrate, wherein the panel, the intermediate substrate and the bottom substrate are stacked in sequence, and the panel and the intermediate substrate together enclose an air intake chamber, and the panel is provided with a plurality of spray holes connected to the air intake chamber; the bottom substrate and the intermediate substrate are fixedly connected by vacuum brazing.

[0007] Wherein, the intermediate substrate is further provided with a groove, a heating wire is arranged in the groove, and the heating wire is fixedly connected in the groove by vacuum brazing.

[0008] Wherein, a baffle is also provided in the air inlet chamber, and the baffle is fixedly connected to the intermediate substrate by electron beam welding.

[0009] Among them, a base handle is vertically connected to the bottom center position of the bottom substrate, an air intake pipe is passed through the base handle, the air intake pipe is connected to the air intake chamber, and the upper end of the air intake pipe is located directly below the baffle.

[0010] Wherein, the panel and the intermediate substrate are fixed by electron beam welding.

[0011] Wherein, the upper portion of the air intake pipe is fixed to the intermediate substrate by electron beam welding.

[0012] Wherein, the panel includes: an outer layer plate, a middle layer plate and an inner layer plate which are welded and fixedly connected in sequence, the middle layer plate is located between the outer layer plate and the inner layer plate, the outer layer plate and the inner layer plate are made of a first-series aluminum material, and the middle layer plate is made of a sixth-series aluminum material.

[0013] Wherein, the panel includes: an outer layer plate, a middle layer plate and an inner layer plate which are welded and fixedly connected in sequence, the middle layer plate is located between the outer layer plate and the inner layer plate, the outer layer plate and the inner layer plate are made of a series of aluminum materials, and the middle layer plate is made of nickel or titanium materials.

[0014] The outer plate, the middle plate and the inner plate have a disc diameter ranging from 250 to 500 mm, and a disc thickness ranging from 1 to 100 mm.

[0015] Wherein, the intermediate substrate and the bottom substrate both include a base body made of a third-series aluminum material and a surface layer made of a first-series aluminum material welded to the surface of the base body.

[0016] The semiconductor back side deposition base of the present invention fixes the bottom substrate and the middle substrate, and the heating wire and the middle substrate of the base by vacuum brazing, thereby solving the problem of deformation of the spray plate caused by uneven stress between components due to repeated heating during long-term use. Other components are fixed by electron beam welding, solving the problem of easy generation of microparticles by the spray plate.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following preferred embodiments are specifically cited and described in detail as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. 4 is a side view of a semiconductor backside deposition pedestal according to an embodiment of the present invention.

[0019] Figure 2 It is a longitudinal cross-sectional view of a semiconductor backside deposition base according to an embodiment of the present invention.

[0020] Figure 3 for Figure 2 Schematic diagram of the enlarged structure of local A in the middle.

[0021] Figure 4 for Figure 2 Schematic diagram of the decomposition is shown.

[0022] Figure 5 It is a schematic diagram of one implementation structure of a panel portion of a semiconductor backside deposition base according to an embodiment of the present invention.

[0023] Description of reference numerals:

[0024] Semiconductor back side deposition base 100, panel 1, intermediate substrate 2, bottom substrate 3, base handle 4, air inlet pipe 5, heating wire 6, baffle 7, spray hole 101, air inlet chamber 10, outer plate 11, middle plate 12 and inner plate 13, groove 21. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships described in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0028] 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 "plurality" is two or more, unless otherwise clearly and specifically defined.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0031] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0032] In the prior art, there is a process that requires depositing a thin film on the back of a wafer, wherein the key mechanism is a base with spraying and heating. In the prior art, the whole base is generally welded by rotary friction welding or EB (electron beam welding) using three-series aluminum materials.

[0033] However, in the above-mentioned base mechanism design, the base needs to be repeatedly heated and cooled during use. In the prior art, all components are fixedly connected by rotary friction welding or electron beam welding, which will cause uneven thermal stress generated by the heat energy transferred by the heating wire, further causing deformation of the base. The deformed base will affect the quality of thin film deposition. In order to solve the above-mentioned problems, this embodiment discloses a semiconductor backside deposition base 100.

[0034] See also Figures 1 to 5This embodiment discloses a semiconductor backside deposition pedestal 100, which is installed in a process chamber of a semiconductor device. The wafer is in the process chamber, and its back side is subjected to thin film deposition through the semiconductor backside deposition pedestal. The semiconductor backside deposition pedestal 100 comprises: a spray panel assembly, a base handle 4 connected to the bottom center of the spray panel assembly, and an air inlet pipe 5 embedded in the base handle 4. The semiconductor backside deposition pedestal 100 is used to uniformly input process gas into the process chamber, so that the process gas is deposited on the back side of the wafer. Among them, the spray panel assembly is provided with an air inlet chamber 10, and the air inlet chamber 10 is also provided with a baffle 7, the air inlet pipe 5 is connected to the air inlet chamber 10, and the upper end of the air inlet pipe 5 is located below the baffle 7, and the process gas input through the air inlet pipe 5 is blocked at the bottom surface of the baffle 7 so as to diffuse to the periphery, and then output from the spray hole 101 of the panel 1 after diffusion. The spray panel assembly includes a panel 1 located at the outermost layer, and the panel 1 is made of a nickel alloy material. The panel 1 is the part that directly contacts the process gas, etc., and the nickel alloy material is used. Compared with the existing aluminum material, the nickel alloy is not easily fluorinated by nitrogen trifluoride at 400 degrees Celsius, and unstable fluoride powder will not be generated. This solves the problem that the existing aluminum spray plate is easily fluorinated to produce fluoride powder that pollutes the process chamber.

[0035] Please refer again Figure 2 The spray panel assembly also includes: an intermediate substrate 2 located below the panel 1 and a bottom substrate 3 located below the intermediate substrate 2; the intermediate substrate 2 and the panel 1 enclose the air intake chamber 10, a heating wire 6 is also embedded in the intermediate substrate 2, and the panel 1 is provided with a plurality of spray holes 101 connected to the air intake chamber 10.

[0036] The bottom substrate 3 and the middle substrate 2 are fixedly connected by vacuum brazing, and the vacuum brazing method can reduce the uniformity of stress changes during heating and cooling, thereby avoiding deformation.

[0037] The panel 1, the middle substrate 2 and the bottom substrate 3 are stacked and welded in sequence from top to bottom to form a spray plate that can homogenize the process gas. The spray plate after welding and fixing has a disc-shaped structure as a whole.

[0038] The heating wire 6 is embedded in the bottom surface of the intermediate substrate 2. The heating wire 6 can be spiral-shaped or radially embedded near the bottom surface of the intermediate substrate 2. The heating wire 6 is energized to generate heat, and the heat is transferred to the intermediate substrate 2, and then transferred to the process gas input into the air inlet chamber 10 through the intermediate substrate 2. The process gas delivered to the air inlet chamber 10 is heated and then output from the spray hole 101 of the panel 1 to the process chamber of the semiconductor processing equipment. Specifically, the lower plate surface of the intermediate substrate 2 is provided with a groove 21, and the heating wire 6 is welded in the groove 21 by vacuum brazing. Vacuum brazing is used between the heating wire 6 and the intermediate substrate 2 to increase its thermal stress, thereby avoiding desoldering and deformation of the intermediate substrate 2 and the heating wire 6.

[0039] The middle substrate 2 and the bottom substrate 3 are both provided with through holes for passing an air inlet pipe 5, and the air inlet pipe 5 directly delivers the process gas delivered from the outside to the air inlet chamber 10. The central axis of the air inlet pipe 5 is coaxial with the middle substrate 2 and the bottom substrate 3.

[0040] In this embodiment, the panel 1, the middle substrate 2 and the bottom substrate 3 are all disc structures, the baffle 7 is also a disc structure, and the diameters of the panel 1, the middle substrate 2 and the bottom substrate 3 are substantially the same, and the baffle 7, the base handle 4 and the air inlet pipe 5 are all coaxially connected to the spray panel assembly. On the one hand, the uniformity of the temperature rise of the process gas in the air inlet chamber 10 can be improved, and on the other hand, the uniformity of the process gas output from the panel 1 can also be improved.

[0041] See also Figure 5 In one embodiment, the panel 1 includes: an outer layer plate 11, a middle layer plate 12 and an inner layer plate 13 which are welded and fixedly connected in sequence, the middle layer plate 12 is located between the outer layer plate 11 and the inner layer plate 13, the outer layer plate 11 and the inner layer plate 13 are made of a first-series aluminum material, and the middle layer plate 12 is made of a sixth-series aluminum material or a third-series aluminum material.

[0042] In another embodiment, the panel 1 also includes: an outer layer plate 11, a middle layer plate 12 and an inner layer plate 13 which are welded and fixedly connected in sequence, the middle layer plate 12 is located between the outer layer plate 11 and the inner layer plate 13, the outer layer plate 11 and the inner layer plate 13 are made of a series of aluminum materials, and the middle layer plate 12 is a disc plate made of nickel or titanium.

[0043] In this embodiment, the outer plate 11 and the inner plate 13 are made of a series of aluminum with good surface treatment, or other fluorination-resistant materials, mainly to prevent fluorination by nitrogen trifluoride. The middle plate 12 is made of a series of aluminum or a series of aluminum with high strength, or a high-strength material such as titanium or nickel, mainly to play a supporting role and reduce its thermal deformation.

[0044] The outer plate 11, the middle plate 12 and the inner plate 13 are welded by electron beam welding, tungsten inert gas welding, metal inert gas shielded welding, gas welding, laser welding, stir friction welding and vacuum brazing. The panel 1 composed of the outer plate 11, the middle plate 12 and the outer plate 13 welded together can be connected to the intermediate substrate 2 by welding or screwing.

[0045] Specifically, the spray panel assembly is a disc structure, the air inlet pipe 5 is a circular hollow pipe, the base handle 4 is a round rod structure, and the spray panel assembly is coaxially fixedly connected with the air inlet pipe 5 and the base handle 4. That is, the base handle 4 and the air inlet pipe 5 are vertically connected to the spray panel assembly, and the base handle 4 and the air inlet pipe 5 are connected to the center position of the bottom substrate 3 so that the two are coaxial.

[0046] The outer plate 11, the middle plate 12 and the inner plate 13 have a disc diameter ranging from 250 to 500 mm, and a disc thickness ranging from 1 to 100 mm.

[0047] In this embodiment, the baffle 7 and the intermediate substrate 2 are fixedly connected by electron beam welding, also known as EB welding.

[0048] The heating wire 6 is fixedly connected to the intermediate substrate 2 by brazing, and the bottom substrate 3 is fixedly connected to the intermediate substrate 2 by vacuum brazing. The air inlet pipe 5 is connected to the intermediate substrate 2 by electron beam welding. The bottom substrate 3 is connected to the base handle 4 by electron beam welding.

[0049] The advantages of using multiple welding methods are: the deformation of the base after heating will cause bulging in the middle, and the welding position of the heating wire 6 is placed on the outside, so that the weld will not crack due to deformation. Brazing solves the problem of uneven thermal stress caused by heat transfer in the heating wire 6 area, which leads to deformation during long-term use. Electron beam welding (also known as EB welding) is used between the middle substrate 2, the bottom substrate 3, the air inlet pipe 5 and the base handle 4 of the panel 1 to solve the problem of microparticles generated in the process cavity due to fluorination caused by brazing or rotary friction welding.

[0050] In another embodiment, the intermediate substrate 2 and the bottom substrate 3 both include a base body made of a three-series aluminum material and a surface layer made of a first-series aluminum material welded to the surface of the base body. That is, the intermediate substrate 2 and the bottom substrate 3 are both welded and assembled from two plates of different materials, thereby taking into account the characteristics of different materials, reducing the generation of fluorinated powder, and maintaining the necessary strength and reducing deformation.

[0051] The semiconductor backside deposition base of this embodiment uses vacuum brazing to fix the bottom substrate and the middle substrate, and the heating wire and the middle substrate of the base, so as to solve the problem of deformation caused by uneven stress between the components due to repeated heating during long-term use of the spray plate. Electron beam welding is used to fix other components to solve the problem of microparticles easily generated by the spray plate. In addition, the layers of the spray panel assembly are made of nickel alloy or titanium alloy or a combination structure design combining the characteristics of first-series aluminum and third-series aluminum. On the one hand, it prevents the base from being entangled with fluorinated powder and contaminating the process chamber, and at the same time adopts different welding processes to improve the strength and corrosion resistance of the base.

[0052] The above examples are only used to further illustrate the technical content of the present invention, so that readers can understand it more easily, but they do not mean that the implementation of the present invention is limited to this. Any technical extension or re-creation made according to the present invention is protected by the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A semiconductor backside deposition pedestal, characterized in that: include: A panel, an intermediate substrate and a bottom substrate, wherein the panel, the intermediate substrate and the bottom substrate are stacked in sequence, and an air intake chamber is enclosed between the panel and the intermediate substrate. The panel is provided with a plurality of spray holes connected to the air intake chamber; the bottom substrate and the intermediate substrate are fixedly connected by vacuum brazing.

2. The semiconductor backside deposition pedestal according to claim 1, characterized in that: The intermediate substrate is also provided with a groove, in which a heating wire is provided. The heating wire is fixedly connected to the groove by vacuum brazing.

3. The semiconductor backside deposition pedestal according to claim 2, characterized in that: The air inlet chamber is also provided with a baffle, which is fixedly connected to the intermediate substrate by electron beam welding.

4. The semiconductor backside deposition pedestal according to claim 3, characterized in that: A base handle is also vertically connected to the bottom center of the bottom substrate, an air intake pipe is passed through the base handle, the air intake pipe is connected to the air intake chamber, and the upper end of the air intake pipe is located directly below the baffle.

5. The semiconductor backside deposition pedestal according to claim 4, characterized in that: The panel and the intermediate substrate are fixed by electron beam welding.

6. The semiconductor backside deposition pedestal according to claim 5, characterized in that: The upper portion of the air intake pipe is fixed to the intermediate substrate by electron beam welding.

7. The semiconductor backside deposition pedestal according to any one of claims 1 to 6, characterized in that: The panel comprises: an outer plate, a middle plate and an inner plate which are welded and fixedly connected in sequence, the middle plate is located between the outer plate and the inner plate, the outer plate and the inner plate are made of first series aluminum material, and the middle plate is made of sixth series aluminum material.

8. The semiconductor backside deposition pedestal according to any one of claims 1 to 6, characterized in that: The panel comprises: an outer plate, a middle plate and an inner plate which are welded and fixedly connected in sequence, the middle plate is located between the outer plate and the inner plate, the outer plate and the inner plate are made of a series of aluminum materials, and the middle plate is made of nickel or titanium.

9. The semiconductor backside deposition pedestal according to claim 8, characterized in that: The outer plate, the middle plate and the inner plate have a disc diameter ranging from 250 to 500 mm and a disc thickness ranging from 1 to 100 mm.

10. The semiconductor backside deposition pedestal according to claim 2, characterized in that: The intermediate substrate and the bottom substrate both include a base body made of a third-series aluminum material and a surface layer made of a first-series aluminum material welded to the surface of the base body.

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