Heating pipe structure

Abstract

The invention relates to the technical field of semiconductor manufacturing equipment, and discloses a heating tube structure which comprises a terminal pin and a heating element arranged in a metal protection tube, the metal protection tube is filled with electrical insulation powder, the tail section, connected with the heating element, of the terminal pin is provided with a limiting part, and the heating element is in limiting connection with the limiting part in the axial direction. The terminal pins and the tail sections of the terminal pins form inclined step surfaces. The limiting part limits the axial movement of the heating element so as to prevent the heating element from sliding out of the terminal pin, and the electrical insulation powder filled in the metal protection tube also has a pressing effect on the heating element and the terminal pin, so that the radial direction of the heating element is limited, and the connection tightness of the heating element and the limiting part is further ensured; after the sheath heater is bent, the temperature of each part of the heating element is kept uniform and consistent, and the chemical vapor deposition effect of a semiconductor wafer is improved; when the sheath heater is bent, the inclined step surface can reduce the fracture phenomenon caused by stress.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing equipment, and more specifically, to a heating tube structure. Background Art

[0002] The semiconductor thin film process is a process of depositing materials on the surface of a wafer by physical or chemical means; in the chemical vapor deposition process of a semiconductor wafer, various metal heaters including aluminum and ceramic heaters are usually used as heating elements for the semiconductor wafer. The sheathed heater 7 in the metal heater is arranged in the heating block 8. The metal protection tube material of the sheathed heater 7 usually adopts Inconel alloy or stainless steel series. Since the material of the heating block 8 is a metal with good conductivity, the hot wire in the heating block 8 is a sheathed heater type that ensures electrical insulation from the heating block.

[0003] The sheathed heater 7 inserts a heating element into a metal protection tube. To ensure electrical insulation between the heating element and the metal protection tube, magnesium oxide powder is filled in the metal protection tube and then tightly compressed by rolling and swaging processes. To enable the magnesium oxide inside the metal protection tube to be tightly compressed, the strength of the metal protection tube material needs to reach a certain level, and a suitable metal protection tube material is selected according to the use environment of the sheathed heater 7.

[0004] Currently, the problems existing in the prior art are that before the prepared sheathed heater 7 is inserted into the heating block, it is necessary to bend the straight-shaped sheathed heater 7 according to the hot wire pattern required by the metal heater. However, when bending, two problems usually occur: the first is the open circuit fault. Since the step part A at the end of the power lead is at a right angle, when the sheathed heater 7 is bent, stress concentration occurs at the step part A, resulting in fracture and thus triggering an open circuit fault; the second is that when the sheathed heater 7 is bent, part of the heating element connected to the end part of the power lead will slide out, that is, part of the heating element will be separated from the end part, resulting in a stretching phenomenon, so that the coil pitch of the heating element cannot be kept consistent everywhere, the pitch of the coils at the stretching position becomes larger, the calorific value will decrease, the uniformity of the heating temperature of the sheathed heater 7 at each place is inconsistent, and thus the heating temperature at a certain place of the heating block decreases, leading to a decrease in the uniformity of the heating temperature of the semiconductor wafer.

[0005] Therefore, it is necessary to propose a heating tube structure to at least partially solve the problems existing in the prior art. Summary of the Invention

[0006] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further elaborated in the Detailed Description section. The Summary of the Invention section of the present invention is not intended to attempt to define the key features and essential technical features of the claimed technical solution, let alone attempt to determine the protection scope of the claimed technical solution.

[0007] To at least partially solve the above problems, the present invention provides a heating tube structure, including: lead pins and a heating element disposed within a metal protection tube, wherein the metal protection tube is filled with electrical insulation powder, a limiting portion is provided at the end section of the lead pin connected to the heating element, the heating element is axially and limit-connected to the limiting portion, and an inclined stepped surface is formed between the lead pin and its end section.

[0008] Preferably, the limiting portion is a spiral groove provided at the end section of the lead pin, and the heating element is disposed within the spiral groove.

[0009] Preferably, the cross-sectional shape of the spiral groove is triangular or trapezoidal.

[0010] Preferably, the angle between the stepped surface formed between the lead pin and its end section and the axis of the lead pin is 30° to 60°.

[0011] Preferably, the heating element is a heating coil, and the size of the spiral groove corresponds to the inner diameter of the heating coil.

[0012] Preferably, the depth at which the heating coil is disposed within the spiral groove is greater than or equal to half of the wire diameter of the heating coil.

[0013] Preferably, the number of turns of the heating element wound within the spiral groove is at least three turns.

[0014] Preferably, the length of the end section of the lead pin is at most half of the length of the lead pin inserted into the metal protection tube.

[0015] Preferably, the axis of the heating element is collinear with the axis of the metal protection tube.

[0016] Preferably, the electrical insulation powder is magnesium oxide powder.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] For the heating tube structure of the present invention, a limiting portion is provided at the end section of the lead pin, the heating element is connected to the limiting portion to limit the axial movement of the heating element, so as to prevent the heating element from slipping out of the lead pin. Moreover, the electrical insulating powder filled inside the metal protection tube also has a pressing effect on the heating element and the lead pin, thereby limiting the heating element radially and further ensuring the tight connection between the heating element and the limiting portion. After the sheath heater is bent, the temperature uniformity of each part of the heating element is maintained, the effect of chemical vapor deposition of the semiconductor wafer is improved, and the product quality is guaranteed.

[0019] The end section of the lead pin and the stepped surface formed therewith are inclined surfaces, so as to reduce the fracture phenomenon caused by stress when the sheath heater is bent.

[0020] For the heating tube structure of the present invention, other advantages, objectives and features of the present invention will be partially reflected by the following description, and will also be understood by those skilled in the art through the research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0022] Figure 1 It is a schematic diagram of the connection structure of the lead pin and the heating element when the sheath heater of the prior art is not bent;

[0023] Figure 2 It is a schematic diagram of the connection structure of the lead pin and the heating element when the sheath heater of the prior art is bent;

[0024] Figure 3 It is a schematic diagram of the structure of the stepped portion of the lead pin of the prior art;

[0025] Figure 4 It is a top view structure schematic diagram after the sheath heater is bent;

[0026] Figure 5 It is a side view structure schematic diagram after the sheath heater is bent;

[0027] Figure 6 It is an X-ray scanning schematic diagram at the straight and curve transition of the sheath heater in the prior art;

[0028] Figure 7 It is an X-ray scanning schematic diagram at the curve section of the sheath heater in the prior art;

[0029] Figure 8 It is a schematic diagram of the heating tube structure described in the present invention;

[0030] Figure 9 Schematic diagram of the lead pin structure in the heating tube structure of the present invention;

[0031] Figure 10 Schematic diagram of X-ray scanning at the straight and curve transition of the sheath heater applying the heating tube structure of the present invention;

[0032] Figure 11 Schematic diagram of X-ray scanning at the curve section of the sheath heater applying the heating tube structure of the present invention. Detailed implementation manners

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it according to the description in the specification.

[0034] It should be understood that the terms such as "having", "comprising" and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0035] As Figure 1 shown, it is a schematic diagram of the heating element 2 wound around the lead pin 1 in the prior art. There is no axial limit between the heating element 2 and the lead pin 1 in the figure, and only the electrical insulation powder 4 filled in the metal protection tube 3 presses the heating element 2;

[0036] As Figure 4 and Figure 5 shown, it is the shape of the prepared sheath heater 7 after bending. The bent sheath heater 7 is inserted into the heating block 8;

[0037] As Figure 2 、 Figure 6 and Figure 7 shown, when bending the sheath heater 7 in the prior art, a part of the heating element 2 connected to the lead pin 1 will slide out, resulting in stretching, so that the spacing of the heating coils at this position becomes larger; As Figure 6 and Figure 7 shown, on the bent sheath heater 7, at its straight and curve transition and curve sections, the heating element 2 will be disconnected from the lead pin 1;

[0038] As Figure 3 shown, after the sheath heater 7 in the prior art is bent, the step part A is at a right angle. When the sheath heater 7 is bent, stress concentration occurs at the step part A, resulting in fracture and thus causing a wire breakage fault.

[0039] To solve the above problems in the prior art, as Figure 8As shown in the figure, the present invention provides a heating tube structure, including: lead pins 1 and a heating element 2 disposed within a metal protection tube 3. The metal protection tube 3 is filled with an electrical insulating powder 4. A limiting portion is provided at the end section of the lead pin 1 connected to the heating element 2. The heating element 2 is axially limited and connected to the limiting portion. The lead pin 1 and its end section form an inclined step surface 6.

[0040] Further, the limiting portion can be any structure that can axially limit the heating element 2 while ensuring a stable connection between the heating element 2 and the lead pin 1. The connection between the limiting portion and the heating element 2 can be a snap connection or a fixed connection, etc.

[0041] In the present invention, a limiting portion is provided at the end section of the lead pin 1. The heating element 2 is connected to the limiting portion to limit the axial movement of the heating element 2, preventing the heating element 2 from slipping out of the lead pin 1. Moreover, the electrical insulating powder 4 filled inside the metal protection tube 3 also has a pressing effect on the heating element 2 and the lead pin 1, thereby radially limiting the heating element 2 and further ensuring the tightness of the connection between the heating element 2 and the limiting portion. Thus, after the sheath heater 7 is bent, the temperature uniformity of each part of the heating element 2 is maintained, the effect of chemical vapor deposition of semiconductor wafers is improved, and the product quality is ensured.

[0042] The end section of the lead pin 1 and the step surface 6 formed therewith are set as an inclined surface, so as to reduce the fracture phenomenon caused by stress when the sheath heater 7 is bent.

[0043] As Figure 10 and Figure 11 shown, when the heating tube structure of the present invention is adopted, on the bent sheath heater 7, at the straight and curved transition parts and the curved section, the heating element 2 and the lead pin 1 will not come apart and cause a stretching phenomenon, and the coil spacing consistency of each part of the heating element 2 is relatively good.

[0044] As Figure 9 shown, in one embodiment, the limiting portion is a spiral groove 5 provided at the end section of the lead pin 1, and the heating element 2 is disposed within the spiral groove 5.

[0045] In this embodiment, the spiral groove 5 can be the thread groove of the thread machined on the end section of the lead pin 1. Then, the inclination angle of the end section of the lead pin 1 and the step surface 6 formed therewith is the angle of the thread.

[0046] The heating element 2 is wound within the spiral groove 5, and the axial limit of the heating element 2 is achieved through the spiral protrusion of the thread.

[0047] Further, the cross-sectional shape of the spiral groove 5 is triangular or trapezoidal.

[0048] Both the triangle or trapezoid make the side surface of the spiral groove 5 an inclined surface, which can accommodate the heating element 2, and one end side surface of the spiral groove 5 far from the heating element 2 is the stepped surface 6, so that the stepped surface 6 is an inclined surface.

[0049] In one embodiment, the included angle between the stepped surface 6 formed by the lead pin 1 and its end segment and the axis of the lead pin 1 is 30° to 60°.

[0050] Since the diameter of the lead pin 1 is about 0.5 mm, it is easy to break under stress. Improving the stepped surface 6 from a right angle in the prior art to an angle less than 90° can reduce the fracture phenomenon caused by stress during bending.

[0051] As Figure 8 shown, in one embodiment, the heating element 2 is a heating coil, and the size of the spiral groove 5 corresponds to the inner diameter of the heating coil.

[0052] The heating element 2 is wound on the spiral groove 5, so that the outer diameter of the heating element 2 connected to the lead pin 1 is the same as the outer diameter of the heating element 2 not connected to the lead pin 1, further ensuring the stability of the connection between the heating element 2 and the spiral groove 5.

[0053] As Figure 8 shown, in one embodiment, the depth of the heating coil arranged in the spiral groove 5 is greater than or equal to half of the wire diameter of the heating coil.

[0054] The wire cross-section of the heating coil is circular, and the depth of the wire cross-section in the spiral groove 5 is greater than or equal to half of the wire cross-section diameter, that is, the wire diameter, so that at least half of the wire cross-section of the heating coil is limited in the spiral groove 5, further ensuring the stability of the connection between the heating element 2 and the lead pin 1.

[0055] Furthermore, when determining the depth arranged in the spiral groove 5, the spiral groove 5 is subjected to simulation analysis according to the shape of the spiral groove 5, including: when the shape of the spiral groove 5 is triangular, obtaining the wire diameter of the heating coil and the apex angle of the spiral groove 5, simulating the use of the heating tube, obtaining the structural environment of the heating tube during the simulation use, and determining the coefficient range according to the structural environment of the heating tube, and then further analyzing in combination with the wire diameter of the heating coil, locking the distribution position of the wire diameter of the heating coil, and when the distribution position of the wire diameter of the heating coil is within the coefficient range, determining the coefficient value to obtain the target coefficient value, so as to determine the depth of the spiral groove 5 by combining the wire diameter of the heating coil, the target coefficient value and the apex angle of the spiral groove 5 through the following formula:

[0056]

[0057] In the above formula, H is the depth of the spiral groove 5, d is the wire diameter of the heating coil, k is the target coefficient value, and α is the apex angle of the spiral groove 5;

[0058] When the shape of the spiral groove 5 is trapezoidal, obtain the side inclination angle of the spiral groove 5 (i.e., the inclination angle of the trapezoidal side) and the wire diameter of the heating coil, and determine the depth of the spiral groove 5 by combining the side inclination angle of the spiral groove 5 with the wire diameter of the heating coil through the following formula:

[0059]

[0060] In the above formula, H is the depth of the spiral groove 5, d is the wire diameter of the heating coil, θ is the side inclination angle of the spiral groove 5, and then implement and optimize according to the determined depth of the spiral groove 5 in the production and manufacturing of the heating tube.

[0061] Among them, the structural environment refers to the internal environment of the heating tube structure. During the actual use of the heating tube, the heating coil generates heat inside the heating tube to achieve the purpose of heating the heating tube. Therefore, here, the structural environment of the heating tube usually refers to a high-temperature environment; the above-mentioned determination of the depth of the spiral groove 5 by combining the characteristics of the heating coil and the spiral groove 5 enables different methods to be used for depth determination when the spiral groove 5 is of different shapes, improves the depth adaptation of the heating coil and the spiral groove 5, avoids the heating coil from shaking or moving outside the spiral groove 5, ensures the stability of the heating coil in the spiral groove 5, and enables the spiral groove 5 to better stabilize the heating coil.

[0062] In one embodiment, the number of turns of the heating element 2 wound in the spiral groove 5 is at least three turns.

[0063] The spiral groove 5 at the end of the lead pin 1 is provided with at least three turns, which improves the limiting effect of the spiral groove 5 on the heating element 2 and enables the heating element 2 to be more firmly connected to the lead pin 1.

[0064] In one embodiment, the length of the end section of the lead pin 1 is at most one-half of the length of the lead pin 1 inserted into the metal protection tube 3.

[0065] The length of the lead pin 1 inserted into the metal protection tube 3 and the length of the end section of the lead pin 1 should be appropriately set to prevent the lead pin 1 from slipping in the metal protection tube 3 during bending and causing tension on the heating element 2. The setting of the spiral groove 5 can also increase the contact area between the electrical insulation powder 4 and the lead pin 1 and increase the pressing effect of the electrical insulation powder 4 on the lead pin 1.

[0066] Preferably, the length of the end section of the lead pin 1 is 1 / 100 to 1 / 10 of the length of the lead pin 1 inserted into the metal protection tube 3;

[0067] According to the different sizes of the actual products, the length of the pin wire 1 inserted into the metal protection tube 3 is also different, generally ranging from 100 mm to 1000 mm, while the length of the end section of the lead pin 1 is roughly the same, which is 10 mm.

[0068] In one embodiment, the axis of the heating element 2 is collinear with the axis of the metal protection tube 3.

[0069] Since the distance between the heating element 2 and the metal protection tube 3 is small, it is necessary to ensure that the axis of the heating element 2 is located at the central position (i.e., the axis position) of the metal protection tube 3 to ensure the stability of the position of the heating element 2. The heating element 2 and the metal protection tube 3 are effectively electrically isolated by using the electrical insulation powder 4 to prevent contact between the two after bending.

[0070] In one embodiment, the electrical insulation powder 4 is made of magnesium oxide powder.

[0071] The magnesium oxide powder has high fire-resistant insulation performance, effectively electrically isolating the heating element 2 and the metal protection tube 3, and at the same time being able to withstand the high-temperature heating of the heating element 2.

[0072] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "axial", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0073] In the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communicable with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0074] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the present invention, the present invention is not limited to the specific details and the illustrated examples described herein.

Claims

1. A heating tube structure, characterized in that: include: A lead pin (1) and a heating element (2) arranged in a metal protection tube (3), wherein the metal protection tube (3) is filled with electrical insulating powder (4), a limiting portion is provided at the end where the lead pin (1) is connected to the heating element (2), the heating element (2) and the limiting portion are connected in an axial limiting manner, and the lead pin (1) and its end form an inclined step surface (6).

2. The heating tube structure according to claim 1, characterized in that: The limiting portion is a spiral groove (5) arranged at the end of the lead pin (1), and the heating element (2) is arranged in the spiral groove (5).

3. The heating tube structure according to claim 2, characterized in that: The cross-sectional shape of the spiral groove (5) is triangular or trapezoidal.

4. The heating tube structure according to claim 1, characterized in that: The angle between the step surface (6) formed between the lead pin (1) and its end section and the axis of the lead pin (1) is 30° to 60°.

5. The heating tube structure according to claim 2, characterized in that: The heating element (2) is a heating coil, and the size of the spiral groove (5) corresponds to the inner diameter of the heating coil.

6. The heating tube structure according to claim 5, characterized in that: The depth of the heating coil in the spiral groove (5) is greater than or equal to half of the wire diameter of the heating coil.

7. The heating tube structure according to claim 2, characterized in that: The number of turns of the heating element (2) wound in the spiral groove (5) is at least three.

8. The heating tube structure according to claim 1, characterized in that: The length of the end section of the lead pin (1) is at most one half of the length of the lead pin (1) inserted into the metal protection tube (3).

9. The heating tube structure according to claim 1, characterized in that: The axis of the heating element (2) and the axis of the metal protection tube (3) are arranged colinearly.

10. The heating tube structure according to claim 1, characterized in that: The electrical insulating powder (4) is magnesium oxide powder.

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