TWM677362U - Wafer heaters and chemical vapor deposition systems - Google Patents

Abstract

This invention relates to a wafer heater and a chemical vapor deposition system for solving the technical problem of uneven heat distribution on the surface of a wafer heater. The wafer heater includes: a heating section, including: a lower heating plate, an upper heating plate stacked on the lower heating plate for placing a wafer, and a ceramic heating element embedded between the upper and lower heating plates, the ceramic heating element having a rectangular cross-section, and an interface portion disposed at the bottom of the heating section, the ceramic heating element being configured to be electrically connected to an external power supply via heating element wires extending through the interface portion.

Description

Wafer heaters and chemical vapor deposition systems

This invention relates to the field of chemical vapor deposition technology, and more specifically, to a wafer heater and a chemical vapor deposition system.

Chemical vapor deposition (CVD) is a process that uses gaseous substances to produce chemical and transport reactions on a solid and generate solid deposits. It can help improve the properties of crystals or crystal thin films. Its most common application is to generate new epitaxial single crystal layers on a crystal substrate using a chemical vapor deposition (CVD) system for the manufacture of various microelectronic devices.

Chemical vapor deposition (CVD) systems typically include a reaction chamber and a wafer heater located within the reaction chamber. The wafer heater supports, holds, and heats the wafer (crystal substrate). Achieving a consistent temperature profile on the wafer heater surface is crucial for high-quality thin film deposition.

In related technologies, wafer heaters typically use resistance wires for heating, which are not only prone to damage, leading to significantly increased maintenance and replacement costs, but also cause uneven heat distribution on the wafer heater surface, thus affecting the quality of the thin film formed on the wafer.

The purpose of this invention is to provide a wafer heater and chemical vapor deposition system to solve the technical problem of uneven heat distribution on the surface of the wafer heater.

To achieve the above objectives, this invention provides a wafer heater, comprising: a heating section including: a lower heating plate and an upper heating plate stacked on the lower heating plate for placing a wafer; a ceramic heating element embedded between the upper heating plate and the lower heating plate; the ceramic heating element having a rectangular cross-section; and an interface portion disposed at the bottom of the heating section; the ceramic heating element being configured to be electrically connected to an external power supply via heating element wires extending through the interface portion.

Optionally, the outer surface of the ceramic heating element is coated with an anti-wear coating.

Optionally, the protective coating is an amorphous carbon layer.

Optionally, the heating part further includes a welding preform disposed between the periphery of the upper heating plate and the periphery of the lower heating plate, wherein the upper heating plate and the lower heating plate are welded and fixed by the welding preform.

Alternatively, the ceramic heating element is connected to the heating element wire via a high melting point terminal.

Alternatively, the ceramic heating element may be configured with a structure having multiple concentric circles.

Alternatively, the ceramic heating element is arranged in a serpentine pattern between the upper heating plate and the lower heating plate.

Optionally, the heating part further includes a base plate, the lower heating plate is stacked on the base plate, the interface part is configured as a vertically extending sleeve-shaped structure, the upper end of the interface part is fixedly connected to the base plate, and the end of the ceramic heating element passes through the lower heating plate and the base plate and extends into the interface part to connect with the heating element guide wire.

Optionally, the interface section is further provided with a ceramic shaft, which can insulate the heating element wire.

Based on the above-mentioned technical means, this invention also provides a chemical vapor deposition system, including a reaction chamber and a wafer heater as described in the above-mentioned technical means, wherein the heating part is housed in the reaction chamber and the interface part extends out from the reaction chamber.

Through the aforementioned technical means, the ceramic heating element with a rectangular cross-section provided in this invention is not only less prone to breakage and has good durability, but also has a larger contact area with the upper and lower heating plates. This significantly reduces the thermal resistance between the ceramic heating element and the upper and lower heating plates, thereby making the heat conduction on the wafer surface more efficient and uniform. Furthermore, the absence of air gaps around the periphery of the rectangular cross-section ceramic heating element improves its heat transfer efficiency, enhances heat transfer consistency, and minimizes the risk of localized hot or cold spots. This also improves the uneven heat distribution on the heating section, thereby enhancing the quality of the thin film formed on the wafer. The chemical vapor deposition system provided in this invention has the same technical effect as the wafer heater in the above-mentioned technical means, and will not be described in detail here in order to avoid unnecessary repetition.

Other features and advantages of this invention will be explained in detail in the subsequent section on specific implementation methods.

The following detailed description of the specific embodiments of this invention, in conjunction with the diagrams, is provided. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this invention.

In this work, unless otherwise stated, directional terms such as "up" and "down" generally refer to the upper and lower positions of the wafer heater in normal operating conditions, as shown in Figures 1 to 4. "Inner" and "outer" refer to the inner and outer sides relative to the contours of the corresponding components themselves. Furthermore, when the following description involves diagrams, unless otherwise indicated, the same numbers in different diagrams represent the same or similar elements.

According to a specific embodiment of the present invention, a wafer heater is provided. Referring to Figures 1 to 4, the wafer heater may include a heating section 1 and an interface section 2. The heating section 1 is used to support and heat the wafer 100. The heating section 1 may include a lower heating plate 11, an upper heating plate 12, and a ceramic heating element 13. The upper heating plate 12 may be stacked on the lower heating plate 11 to place the wafer 100, that is, the wafer 100 is supported on the upper surface of the upper heating plate 12. The ceramic heating element 13 may be embedded between the upper heating plate 12 and the lower heating plate 11. The cross-section of the ceramic heating element 13 may be rectangular. The interface section 2 can be disposed at the bottom of the heating section 1. The ceramic heating element 13 can be electrically connected to an external power supply (not shown) and/or a control module (not shown) through the heating element wire 21 passing through the interface section 2, so as to control the heating power of the ceramic heating element 13.

Through the aforementioned technical means, in the wafer heater provided by this invention, the ceramic heating element 13 with a rectangular cross-section is not only less prone to breakage and has good durability, but also has a larger contact area with the upper heating plate 12 and the lower heating plate 11. This significantly reduces the thermal resistance between the ceramic heating element 13 and the upper and lower heating plates 12 and 11, thereby making the heat conduction on the surface of the wafer 100 more efficient and uniform. In addition, there are no air gaps around the periphery of the ceramic heating element 13 with a rectangular cross-section, which can improve the heat transfer efficiency of the ceramic heating element 13, improve heat transfer consistency, and minimize the risk of local hot or cold spots. This improves the uneven heat distribution on the heating section 1, thereby improving the quality of the thin film formed on the wafer 100.

To further improve the uneven heat distribution on the heating section 1, referring to Figure 5, the heating section 1 may include an inner heating area 101 and an annular outer heating area 102. The inner heating area 101 may be located at a position corresponding to the central region of the wafer 100. The annular outer heating area 102 may be generally annular in shape, roughly surrounding the outer side of the inner heating area 101 and concentrically arranged with the inner heating area 101. The temperature of the inner heating area 101 and the annular outer heating area 102 can be controlled separately through the interface section 2 to accurately control the temperature curves of different areas on the heating section 1, so that the heat distribution on the surface of the heating section 1 is uniform, ensuring that the thin film formed on the surface of the wafer 100 has good uniformity and deposition characteristics.

To enable the inner heating zone 101 and the annular outer heating zone 102 to generate heat, referring to FIG5, the ceramic heating element 13 may include a first heating element 131 and a second heating element 132. The first heating element 131 may be disposed in the inner heating zone 101, and the second heating element 132 may be disposed in the annular outer heating zone 102. The first heating element 131 and the second heating element 132 may be respectively connected to the control module via the heating element guide wire 21 passing through the interface portion 2 to realize the separate temperature control of the inner heating zone 101 and the annular outer heating zone 102.

To further improve the durability of the ceramic heating element 13, an anti-wear coating can be applied to the outer surface of the ceramic heating element 13. Specifically, the anti-wear coating can be an amorphous carbon layer. The amorphous carbon layer not only has high hardness, high wear resistance and good toughness to improve the wear resistance of the ceramic heating element 13, but also has high thermal conductivity to improve the heat transfer efficiency of the ceramic heating element 13.

In order to ensure a reliable connection between the upper heating plate 12 and the lower heating plate 11, referring to FIG3, the heating part 1 may further include a welding preform 14 disposed between the periphery of the upper heating plate 12 and the periphery of the lower heating plate 11. The upper heating plate 12 and the lower heating plate 11 can be welded and fixed by welding the welding preform 14 to form a permanent and reliable seal between the upper heating plate 12 and the lower heating plate 11.

To ensure a reliable electrical connection between the ceramic heating element 13 and the heating element wire 21, the ceramic heating element 13 can be connected to the heating element wire 21 via a high melting point terminal (not shown). The high melting point terminal can be made of a material with a high melting point to withstand the high temperature from the ceramic heating element 13 and reduce the risk of failure at the connection point with the heating element wire 21.

Furthermore, a terminal protection cover (not shown) may be provided on the high melting point terminal to prevent damage from external sources.

To ensure a uniform distribution of the ceramic heating element 13 between the upper heating plate 12 and the lower heating plate 11, the ceramic heating element 13 can be configured with a structure having multiple concentric circles. Specifically, referring to Figure 2, the ceramic heating element 13 can be coiled in a serpentine manner between the upper heating plate 12 and the lower heating plate 11, with one sidewall of the ceramic heating element 13 parallel to the upper surface of the upper heating plate 12. This not only ensures that the ceramic heating element 13 is evenly distributed between the upper heating plate 12 and the lower heating plate 11, but also maximizes the contact area between the ceramic heating element 13 and the upper heating plate 12, thereby further improving the uniformity of heat distribution on the upper surface of the upper heating plate 12.

Since the wafer 100 is a circular sheet structure, as shown in Figures 1 and 2, the heating part 1 can also be constructed as a disc structure, that is, both the upper heating plate 12 and the lower heating plate 11 can be disc structures, and the interface part 2 can be located at the center of the bottom of the heating part 1.

In order to facilitate temperature control of the annular outer heating zone 102 through the interface section 2, referring to FIG5, a radially extending clearance notch can be formed on the inner heating zone 101, and a part of the annular outer heating zone 102 can be inserted into the clearance notch to approach the center of the heating section 1.

Correspondingly, the first heating element 131 can be coiled in a serpentine pattern within the inner heating zone 101 to fill the inner heating zone 101, thereby maximizing the heating area of the first heating element 131 within the inner heating zone 101. The second heating element 132 can be coiled in a serpentine pattern within the annular outer heating zone 102 to fill the annular outer heating zone 102, thereby maximizing the heating area of the second heating element 132 within the annular outer heating zone 102.

Referring to Figures 2 to 4, the heating part 1 may also include a base plate 15, and the lower heating plate 11 may be stacked on the base plate 15. The interface part 2 may be constructed as a vertically extending sleeve-shaped structure to facilitate the passage of the wire. The upper end of the interface part 2 may be fixedly connected to the base plate 15. The base plate 15 can separate the interface part 2 from the lower heating plate 11 to reduce the heat transfer from the lower heating plate 11 to the interface part 2, thereby preventing the interface part 2 from malfunctioning due to high temperature. The end of the ceramic heating element 13 may pass through the lower heating plate 11 and the base plate 15 and extend into the interface part 2 to connect with the heating element wire 21.

To prevent the heating element guide wire 21 from transferring heat to the guide wires of other surrounding components, as shown in Figures 3 and 4, a ceramic shaft 22 can also be provided in the interface section 2. The heating element guide wire 21 passes through the ceramic shaft 22, which can insulate the heating element guide wire 21 from heat. The ceramic shaft 22 can be fixed to the inner wall of the interface section 2 by means of a high melting point and high strength plastic.

Based on the above-mentioned technical means, this invention also provides a chemical vapor deposition system. Referring to Figure 1, the chemical vapor deposition system may include a reaction chamber 200 and the wafer heater mentioned above. The heating part 1 can be housed in the reaction chamber 200. The external power supply and/or control module can be located outside the reaction chamber 200 to avoid the high temperature inside the reaction chamber 200 affecting the operation of the control module. The interface part 2 can extend from the reaction chamber 200 so that the wires of each component in the heating part 1 can pass through the interface part 2 to connect to the external power supply and/or control module.

Through the above-mentioned technical means, the chemical vapor deposition system provided by this invention has the same technical effect as the wafer heater in the above-mentioned technical means. In order to avoid unnecessary repetition, it will not be described in detail here.

The above description, in conjunction with the accompanying drawings, details the ideal implementation of this invention. However, this invention is not limited to the specific details described above. Within the scope of the technical concept of this invention, various simple modifications can be made to the technical means of this invention, and all such simple modifications are within the scope of protection of this invention.

It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this work will not describe the various possible combinations separately.

Furthermore, various implementations of this work can be combined in any way, as long as they do not contradict the ideas of this work, and they should also be considered as the disclosed content of this work.

100: Wafer; 200: Reaction Chamber; 1: Heating Section; 101: Inner Heating Zone; 102: Annular Outer Heating Zone; 11: Lower Heating Plate; 12: Upper Heating Plate; 13: Ceramic Heating Element; 131: First Heating Element; 132: Second Heating Element; 14: Soldering Preform; 15: Base Plate; 2: Interface Section; 21: Heating Element Guide Wire; 22: Ceramic Shaft

The drawings are provided to further understand the invention and form part of the specification. They are used in conjunction with the following specific embodiments to explain the invention, but do not constitute a limitation thereof. In the drawings: [Figure 1] Figure 1 is a structural schematic diagram of the chemical vapor deposition system in a specific embodiment of the invention. [Figure 2] Figure 2 is an exploded view of Figure 1. [Figure 3] Figure 3 is a cross-sectional view of the wafer heater in a specific embodiment of the invention from one angle. [Figure 4] Figure 4 is a cross-sectional view of the wafer heater in a specific embodiment of the invention from another angle. [Figure 5] Figure 5 is a schematic diagram showing the distribution of the inner heating zone and the annular outer heating zone of the heating section in a specific embodiment of the invention.

1: Heating section

11: Lower heating plate

12: Upper heating plate

13: Ceramic heating element

14: Welding preforms

15: Base Plate

2: Interface Section

22: Ceramic Shaft

Claims (10)

A wafer heater is characterized in that it includes: a heating section, including: a lower heating plate, an upper heating plate stacked on the lower heating plate for placing a wafer, and a ceramic heating element embedded between the upper heating plate and the lower heating plate, the ceramic heating element having a rectangular cross-section, and an interface portion disposed at the bottom of the heating section, the ceramic heating element being configured to be electrically connected to an external power supply through heating element wires extending from the interface portion. The wafer heater as described in claim 1, wherein the outer surface of the ceramic heating element is coated with a protective coating. The wafer heater as described in claim 2, wherein the protective coating is an amorphous carbon layer. The wafer heater as described in claim 1, wherein the heating part further includes a soldering preform disposed between the periphery of the upper heating plate and the periphery of the lower heating plate, the upper heating plate and the lower heating plate being welded and fixed by the soldering preform. The wafer heater as described in claim 1, wherein the ceramic heating element is connected to the heating element wire via a high melting point terminal. The wafer heater as described in claim 1, wherein the ceramic heating element is configured with a structure having multiple concentric circles. The wafer heater as described in claim 1 or 6, wherein the ceramic heating element is arranged in a serpentine pattern between the upper heating plate and the lower heating plate. The wafer heater as described in claim 1, wherein the heating part further includes a base plate, the lower heating plate is stacked on the base plate, the interface is configured as a vertically extending sleeve-shaped structure, the upper end of the interface is fixedly connected to the base plate, and the end of the ceramic heating element passes through the lower heating plate and the base plate and extends into the interface to connect with the heating element wire. The wafer heater as described in claim 8, wherein the interface portion is further provided with a ceramic shaft that can insulate the heating element wires. A chemical vapor deposition system, characterized in that it includes: a reaction chamber, and a wafer heater as described in any one of claims 1 to 9, the heating portion being housed in the reaction chamber, and the interface portion extending from the reaction chamber.