Pedestal and MOCVD (metal organic chemical vapor deposition) equipment

Abstract

The utility model provides a base and MOCVD (Metal Organic Chemical Vapor Deposition) equipment. The base comprises a carrying disc which comprises a supporting face and a side face surrounding the supporting face in the circumferential direction; a groove is formed in the supporting surface, at least one end of the groove penetrates through the side surface, and the groove is used for accommodating at least part of the structure of a mechanical arm for transferring a wafer; a wafer; and the heating element is arranged in an area, which is not provided with the groove, of the supporting surface. According to the utility model, the groove capable of accommodating the partial structure of the mechanical arm is arranged on the carrying disc, so that the mechanical arm can successfully place the wafer on the supporting surface and safely withdraw the wafer, a liftable supporting column in the original structure is removed, the temperature uniformity on the carrying disc is improved, and the uniformity of the deposition rate of a thin film on the wafer is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of deposition equipment, in particular to a base and MOCVD equipment. Background Art

[0002] Metal-organic chemical vapor deposition (MOCVD) is a new type of vapor phase epitaxial growth technology developed on the basis of vapor phase epitaxy. It is a chemical vapor deposition process that uses metal organic compounds as source materials. Using the MOCVD process, many nanolayers can be deposited with extremely high precision, and each layer has a controllable thickness to form materials with specific optical and electrical properties.

[0003] like Figure 1 As shown, the base in the reaction chamber of the conventional MOCVD equipment includes a carrier plate 1' and a heating element 2' located on the carrier plate 1'. The heating element 2' is used to receive electricity to generate heat to heat the wafer. The rate of film deposition is related to the temperature uniformity on the wafer. Therefore, the temperature uniformity on the carrier plate 1' is very important to the uniformity of the film deposited on the wafer. Figure 1 and Figure 2 As shown, the surface of the carrier 1' is also formed with a hole 3', and a support rod 4' is arranged in the hole 3'. The support rod 4' can receive the wafer 6 by rising, and then the robot arm withdraws to the wafer taking position, and the support rod 4' descends to further transfer the wafer 6' to the carrier 1'. When the TiN (titanium nitride) film is deposited using the existing equipment, such as Figure 3 As shown, the position where the wafer 6' contacts the four support rods 4' ( Figure 3 The square resistance of titanium nitride (at the position indicated by the middle circle) is obviously too small. The resistance of the film is related to the film thickness. The square resistance of a uniform film will decrease as the thickness increases. Therefore, the square resistance of the four support rods 4' will be significantly smaller than that of the nearby area. This is because the support rods 4' have a high conductivity, so the temperature of the corresponding area of ​​the wafer 6' in contact with it is high, which significantly increases the film deposition rate at this location. The high deposition rate causes the thickness of the deposited film to be too large, and the resistance of the thicker film is reduced. In the contact window process, TiN is used as an isolation layer. The thickness of TiN is extremely thin (approximately 25A to 100A), and the uniformity of TiN is extremely high. When the existing MOCVD equipment grows TiN thin films, it will inevitably affect the uniformity of TiN, which may lead to differences in the electrical properties of the wafer contact window.

[0004] Therefore, it is necessary to improve the film deposition rate at the support rods 4 ′ on the carrier 1 ′. Utility Model Content

[0005] In view of the problems in the prior art, the purpose of the utility model is to provide a susceptor and MOCVD equipment to improve the uniformity of temperature distribution of wafers and improve the uniformity of thin film deposition rate on wafers.

[0006] The utility model provides a base, comprising:

[0007] The carrier comprises a supporting surface and a side surface surrounding the supporting surface; a groove is provided on the supporting surface, at least one end of the groove passes through the side surface, and the groove is used to accommodate at least a part of the structure of a robotic arm for transferring wafers;

[0008] The heating element is arranged in an area of ​​the support surface where the groove is not arranged.

[0009] In some embodiments, the groove includes two rectangular grooves parallel to each other.

[0010] In some embodiments, the groove includes two rectangular grooves arranged along the radial direction of the carrier.

[0011] In some embodiments, the depth of the groove is less than 1 cm, and the width of the groove is less than 1 cm.

[0012] In some embodiments, the heating element includes a plurality of concentric circle patterns, each of the concentric circle patterns includes an arc portion extending along a circumferential direction and a folded portion connecting the arcs.

[0013] In some embodiments, the heating element is configured in the form of a single heating zone connected to one power terminal pair to generate heat.

[0014] In some embodiments, the heating element is configured in the form of multiple heating zones, each of which is independently connected to different power terminal pairs to generate heat according to different specified areas.

[0015] An embodiment of the utility model further provides a MOCVD device, comprising a base and a robot arm as described in any one of the above items, wherein the robot arm is used to transfer the wafer, and at least a portion of the robot arm can be accommodated in the groove.

[0016] In some embodiments, the groove includes two rectangular grooves, the robotic arm includes a first supporting portion, a second supporting portion, and a connecting portion connecting the first supporting portion and the second supporting portion, and at least part of the first supporting portion and the second supporting portion can be accommodated in the rectangular grooves.

[0017] In some embodiments, the distance between the first supporting portion and the second supporting portion is 130 mm to 140 mm.

[0018] The susceptor and MOCVD equipment provided by the utility model have the following advantages:

[0019] The base includes: a carrier, including a support surface and a side surface surrounding the support surface; a groove is provided on the support surface, at least one end of the groove passes through the side surface, and the groove is used to accommodate at least a partial structure wafer of a robotic arm for transferring wafers; a heating element is arranged in an area of ​​the support surface where the groove is not arranged. The utility model provides a groove on the carrier that can accommodate a partial structure of the robotic arm, so that the robotic arm can successfully place the wafer on the support surface and withdraw it safely, eliminating the use of a liftable support column in the original structure to place the wafer on the carrier, thereby improving the temperature uniformity of the carrier, and further improving the uniformity of the thin film deposition rate on the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, objectives and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings.

[0021] Figure 1 It is a schematic diagram of a susceptor in an MOCVD device in the prior art;

[0022] Figure 2 Yes Figure 1 Schematic diagram of placing a wafer on a base in FIG.

[0023] Figure 3 Is Figure 1 The resistance mapping diagram of the TiN film deposited on the wafer by the base;

[0024] Figure 4 It is a schematic diagram of a base of an embodiment of the utility model;

[0025] Figure 5 Yes Figure 4 Schematic diagram of the robotic arm used to transfer wafers;

[0026] Figure 6 yes Figure 5 Schematic diagram of a robotic arm placing a wafer;

[0027] Figure 7 Yes Figure 5 Schematic diagram of the robotic arm being placed downward into the groove;

[0028] Figure 8 Is adopted Figure 3 The base deposits the resistance mapping of TiN film on the wafer.

[0029] Reference numerals:

[0030] 1' Carrier plate in the prior art 2 Heating element

[0031] 2' Heating element in the prior art 5 Robotic arm

[0032] 3' Hole 51 in the prior art First support portion

[0033] 4' The second support portion of the support rod 52 in the prior art

[0034] 6' Wafer 53 connection part in the prior art

[0035] 1 tray 6 wafers

[0036] 11 Grooves DETAILED DESCRIPTION

[0037] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. In the figures, the same reference numerals represent the same or similar structures, and thus their repeated description will be omitted. "or" and "or" in the specification may both mean "and" or "or".

[0038] In order to solve the problem that the support column in the MOCVD equipment in the prior art will cause the deposition rate at the contact position between the support column and the wafer to increase, thereby reducing the thickness uniformity of the thin film on the wafer, the embodiment of the utility model provides a base, including: a carrier, including a supporting surface and a side surface surrounding the supporting surface; a groove is provided on the supporting surface, at least one end of the groove passes through the side surface, and the groove is used to accommodate at least a partial structural wafer of a robot arm for transferring the wafer; a heating element is arranged on the area of ​​the supporting surface where the groove is not provided.

[0039] By setting a groove on the carrier, the robotic arm carrying the wafer can descend and part of its structure falls into the groove, so that the wafer can be safely placed on the carrying surface and safely withdrawn to the original position where the wafer was grabbed. The liftable support column on the original base can be eliminated, thereby improving the problem of uneven temperature on the wafer caused by the original support column, which in turn leads to uneven thickness of thin film deposition.

[0040] The utility model also provides a MOCVD device including the above-mentioned base, which can achieve the technical effect of the above-mentioned base and improve the problem of uneven film deposition thickness caused by uneven wafer temperature caused by the original support column.

[0041] The base and the mechanical arm in the specific embodiment will be explained in detail below in conjunction with the accompanying drawings. It should be understood that the accompanying drawings and the following description are only examples and are not intended to limit the scope of protection of this application.

[0042] like Figures 4 to 7 As shown, the embodiment of the utility model provides a base, including: a carrier plate 1 and a heating element 2. The carrier plate 1 includes a supporting surface and a side surface surrounding the supporting surface, and a groove 11 is provided on the supporting surface, and at least one end of the groove 11 passes through the side surface, and the groove 11 is used to accommodate at least part of the structure of the robot arm 5 for transferring the wafer 6; the heating element 2 is arranged in the area of ​​the supporting surface where the groove 11 is not arranged, so as to heat the wafer 6.

[0043] By setting a groove 11 on the carrier 1, the robot arm 5 carrying the wafer 6 falls into the groove 11 through a descending movement, so that the wafer can be safely placed on the carrying surface. Therefore, the liftable support column on the original base can be eliminated, and the problem of uneven film deposition thickness caused by uneven temperature of the wafer 6 caused by the original support column can be improved.

[0044] The specific material of the base can be ceramic material. The material of the wafer 6 can be silicon wafer, glass or sapphire and other materials.

[0045] In this embodiment, the groove 11 includes two rectangular grooves parallel to each other. In some embodiments, the groove 11 includes two rectangular grooves arranged along the radial direction of the carrier 1. The specific shape of the groove 11 can be set according to the actual robot arm, and is not specifically limited here. The depth of the groove 11 can be set to be less than 1 cm, such as 0.3 cm, 0.6 cm, 0.9 cm; the width of the groove 11 is less than 1 cm, such as 0.3 cm, 0.6 cm, 0.9 cm.

[0046] The heating element 2 includes a plurality of concentric circle patterns, each of which includes an arc portion extending in a circumferential direction and a folded portion connecting the arcs. The heating element 2 can form a plurality of concentric circle patterns by a heating wire. In some embodiments, the heating element 2 can be formed into a multilayer structure to accurately control the temperature.

[0047] In some embodiments, the heating element 2 can be configured as a whole heating zone, that is, the heating element 2 is connected as a whole to a power supply terminal (such as an AC or DC power supply) to generate heat. The entire heating element 2 is connected to a power supply terminal, which can simplify the configuration process of the heating element 2 and the power supply.

[0048] In other embodiments, the heating element 2 is configured in a plurality of heating zones, that is, the pattern of the heating components is independently connected to different power terminals for heating according to the specified areas. Each zone can independently control the heating temperature of the heating element 2 in its heating zone.

[0049] like Figures 5 to 7 As shown, an embodiment of the utility model further provides a MOCVD device, comprising a base as described in any one of the above items and a robot arm 5 , wherein the robot arm 5 is used to transfer a wafer 6 , and at least a portion of the robot arm 5 can be accommodated in a groove 11 .

[0050] The groove 11 includes two parallel rectangular grooves, and the robot arm 5 includes a first support portion 51, a second support portion 52, and a connecting portion 53 connecting the first support portion 51 and the second support portion 52, and at least part of the first support portion 51 and the second support portion 52 can be accommodated in the rectangular groove 11. In some embodiments, the first support portion 51 and the second support portion 52 include an adsorption portion with negative pressure, so that the wafer is sucked tightly on the robot arm 5 to prevent the wafer 6 from falling when transferring.

[0051] The specific steps of the robot arm 5 placing the wafer 6 on the carrier 1 are as follows:

[0052] like Figure 6 As shown, the robot arm 5 first absorbs the wafer 6 and then moves to the top of the carrier 1, and then slowly descends to make the first support part 51 and the second support part 52 fall into the groove 11.

[0053] like Figure 7 As shown, the first support part 51 and the second support part 52 are withdrawn from the groove 11 in a radial direction away from the carrier plate 1. Then, after the wafer 6 falls on the carrier plate 1, the back pressure of the air is blown for overall preheating, which effectively ensures uniform heating, thereby improving the film deposition rate on the wafer 6 and improving the uniformity of the thickness of the film deposited on the wafer 6.

[0054] In some embodiments, the distance between the first support portion 51 and the second support portion 52 is 130 mm to 140 mm, and can be 132 mm, 134 mm, 136 mm, or 138 mm, for example. In some embodiments, the width of the first support portion 51 and the second support portion 52 is 5 mm, and the thickness is 5 mm, which can ensure that the first support portion 51 and the second support portion 52 fall into the above-mentioned groove 11. The specific width, thickness, and height of the robot arm 5 need to be set according to the corresponding groove 11, and those skilled in the art can set it according to actual needs, which is not specifically shown here.

[0055] To compare the film uniformity of the existing MOCVD equipment and the MOCVD equipment provided by the embodiment of the utility model, as shown in FIG. Figure 8As shown, a resistance mapping diagram of the TiN film deposited by the MOCVD equipment provided in an embodiment of the utility model is shown. From the figure, it can be seen that the resistance at the outermost circle of the wafer 6 is not obviously too small, indicating that the film thickness on the outermost circle of the wafer 6 is relatively uniform at this time. Therefore, the existing MOCVD equipment improves the uniformity of the thin film deposited on the wafer 6.

[0056] The susceptor and MOCVD equipment provided by the utility model have the following advantages:

[0057] The base comprises: a carrier, comprising a support surface and a side surface surrounding the support surface; a groove is provided on the support surface, at least one end of the groove passes through the side surface, and the groove is used to accommodate at least part of the structure of a robotic arm for transferring wafers; a heating element is arranged in an area of ​​the support surface where the groove is not arranged. The utility model provides a groove on the carrier that can accommodate part of the structure of the robotic arm, so that the robotic arm can successfully place the wafer on the support surface and withdraw it safely, eliminating the liftable support column in the original structure, improving the temperature uniformity of the carrier, and further improving the uniformity of the thin film deposition rate on the wafer.

[0058] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A base, characterized in that: include: The carrier comprises a supporting surface and a side surface surrounding the supporting surface; a groove is provided on the supporting surface, at least one end of the groove passes through the side surface, and the groove is used to accommodate at least a part of the structure of a robotic arm for transferring wafers; The heating element is arranged in an area of ​​the support surface where the groove is not arranged.

2. The base according to claim 1, characterized in that: The groove comprises two rectangular grooves which are parallel to each other.

3. The base according to claim 1, characterized in that: The groove comprises two rectangular grooves arranged along the radial direction of the carrier.

4. The base according to claim 2 or 3, characterized in that: The depth of the groove is less than 1 cm, and the width of the groove is less than 1 cm.

5. The base according to claim 4, characterized in that: The heating element includes a plurality of concentric circle patterns, each of which includes an arc portion extending along a circumferential direction and a folded portion connecting the arcs.

6. The base according to claim 5, characterized in that The heating element is configured in the form of a single heating zone connected to one power terminal pair to generate heat.

7. The base according to claim 5, characterized in that The heating element is configured in a plurality of heating zones in which the heating elements are independently connected to different power terminal pairs according to different specified areas to generate heat.

8. A MOCVD device, characterized in that: It comprises a base and a robot arm as described in any one of claims 1 to 7, wherein the robot arm is used to transfer the wafer, and at least a part of the robot arm can be accommodated in the groove.

9. The MOCVD device according to claim 8, characterized in that: The groove includes two rectangular grooves, and the robotic arm includes a first supporting portion, a second supporting portion, and a connecting portion connecting the first supporting portion and the second supporting portion, and at least parts of the first supporting portion and the second supporting portion can be accommodated in the rectangular grooves.

10. The MOCVD device according to claim 9, characterized in that: The distance between the first supporting portion and the second supporting portion is 130 mm to 140 mm.

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