Tantalum film preparation device capable of detecting resistivity on line

Abstract

The utility model relates to a tantalum film preparation device capable of detecting resistivity on line, which comprises two chambers, each chamber is provided with a vacuumizing device, a sample conveying channel is arranged between the two chambers, a valve is arranged in the sample conveying channel, the first chamber is provided with a sample inlet and outlet door, and the second chamber is provided with a sample outlet and inlet door. A wafer storage rack, a wafer collection part, a first sample bearing table and a resistivity detection device are arranged in the first cavity, a conveying mechanism is further arranged in the first cavity, and the output end of the conveying mechanism is switched and moved among the wafer storage rack, the wafer collection part, a sample conveying channel and the resistivity detection device; a second sample bearing table, a magnetron sputtering gun device and a crystal oscillator device are arranged in the second cavity, and the device further comprises a return mechanism, so that the process research and development efficiency of a high-quality a-Ta thin film and the production efficiency of a high-quality tantalum thin film are effectively improved; and the new wafer is stored in the vacuum environment, so that the wafer is prevented from being polluted, and the quality of the tantalum film is improved.

Description

Technical Field

[0001] The utility model relates to the field of film manufacturing, in particular to a tantalum film preparation device capable of online resistivity detection. Background Art

[0002] In 2020, the Princeton University research team used α-phase tantalum film (a-Ta) in superconducting quantum chips, which greatly improved the decoherence time of quantum bits, thus achieving a major advancement in the field of superconducting quantum computing. Although the superiority of tantalum film in superconducting quantum bits has been confirmed, due to the diversity of tantalum films, tantalum films prepared by magnetron sputtering equipment will have two different phases, one is a tantalum film with a stable body-centered cubic (bcc) phase, called a-Ta, and the other is a metastable tetragonal phase, called β-Ta (b-Ta). a-Ta film has the characteristics of good toughness, good ductility, low hardness, and low resistivity, and only a-Ta film can improve the decoherence time of quantum bits. The preparation of a-Ta film has strict requirements on process parameters, and the suitable process window is narrow. The prepared tantalum film is often in the β phase (b-Ta) or mixed phase. Therefore, it is an extremely urgent task in the field of superconducting quantum bits in China to achieve the preparation of high-quality a-Ta film as soon as possible.

[0003] However, the current magnetron sputtering equipment can only achieve the growth of tantalum thin films. After the growth of the tantalum thin film is completed, it is necessary to break the vacuum in the chamber to take samples, and then use relevant characterization equipment (such as XRD) and other equipment for characterization testing, and then adjust the process parameters based on the test results.

[0004] The above-mentioned existing method of obtaining a-Ta thin film requires breaking the vacuum inside the chamber, taking out the sample and then testing and analyzing it outside, and then adjusting the process parameters on the equipment. The whole process is time-consuming and labor-intensive, which greatly affects the research progress of high-quality a-Ta thin films, thereby delaying the research and development of superconducting quantum bits. At the same time, this method also increases the detection time and cost of judging tantalum thin films, and requires the equipment to repeatedly extract and release the vacuum, which limits the efficiency of film preparation and process research and development. Utility Model Content

[0005] The utility model aims to provide a tantalum film preparation device capable of online resistivity detection, so as to solve the problems of time-consuming and labor-intensive process exploration and preparation of a-Ta thin film in the prior art.

[0006] In order to solve the above problems, the tantalum thin film preparation device capable of online resistivity detection of the present invention adopts the following technical solutions:

[0007] The preparation device includes two chambers, both chambers are equipped with a vacuum pump, and there is a sample delivery channel between the two chambers. The sample delivery channel is provided with a valve for controlling the isolation and connection between the first chamber and the second chamber. The two chambers are defined as the first chamber and the second chamber respectively. The first chamber has a sample inlet and outlet door. The first chamber is provided with a wafer storage rack for centrally storing a plurality of target wafers, a wafer collection part for collecting target wafers after thin film growth, a first sample carrier for carrying a single target wafer, and a resistivity detection device for detecting the resistivity of the thin film. The first chamber also has a A conveying mechanism is arranged, and the output end of the conveying mechanism switches and moves between the wafer storage rack, the wafer collection part, the sample conveying channel and the resistivity detection device to transport the single target wafer between various positions; the second chamber is arranged with a second sample carrier for carrying the target wafer, a magnetron sputtering gun device for sputtering and depositing Ta film, and a crystal oscillator device for real-time detection of the thickness of the thin film growth, and also includes a feedback mechanism, the output end of the feedback mechanism is used to move back and forth between the first sample carrier and the second sample carrier to transfer the target wafer between the first chamber and the second chamber.

[0008] Furthermore, the wafer collection part and the wafer storage rack are arranged on the peripheral side of the sample inlet and outlet door in the first chamber, the conveying mechanism is arranged at the center of the first chamber, and the resistivity detection device is arranged on the side facing away from the sample inlet and outlet door.

[0009] Furthermore, the first sample carrier platform includes a lifting platform and a lifting mechanism connected to the bottom of the lifting platform. The outer side of the lifting platform is surrounded by a carrier frame. The lifting platform moves downward during the up and down movements to lower the lifting surface to an avoidance position below the upper end surface of the carrier platform. It also moves upward to lift the wafer to a pick-up and place position above the output end of the conveying mechanism and the return mechanism.

[0010] Furthermore, the conveying mechanism includes a wafer handling robot, which includes a main arm and a support arm connected to the main arm, the support arm is composed of two or more single rods hinged to each other in series, the swing axis of the support arm is consistent with the swing axis of the main arm, and the tail end of the support arm is connected to a fork for supporting the bottom side of the target wafer.

[0011] Furthermore, the return mechanism includes a conveying rod guided and assembled in the second chamber, and the tail end of the conveying rod has a front fork for cantilevering to the bottom of the wafer.

[0012] Furthermore, the wafer collecting unit includes a wafer collecting rack arranged in the first chamber, and the wafer collecting rack is used to place target wafers with qualified film resistivity, and target wafers with unqualified resistivity can be placed back on the wafer storage rack.

[0013] Furthermore, the wafer storage rack has two vertical plates, and the opposite side walls of the vertical plates are respectively provided with ribs extending relative to each other. There are a plurality of ribs, which are evenly spaced along the upper and lower directions of the corresponding side walls, and the space between two adjacent ribs constitutes a storage space for placing the target wafer.

[0014] Furthermore, the wafer storage rack includes a frame body with an inverted U-shaped cross-section, and vertical arms on the left and right sides of the frame body constitute the vertical plates.

[0015] Furthermore, the valve is a gate valve.

[0016] Furthermore, the resistivity detection device is a sheet resistance testing device and the sheet resistance measuring instrument is a sheet resistance measuring instrument.

[0017] The beneficial effects of the utility model are as follows: the tantalum thin film preparation device capable of online resistivity detection involved in the utility model creatively introduces two interconnected chambers, and a magnetron sputtering device is arranged in one of the chambers, and a resistivity detection device is arranged inside the other chamber. In actual use, it can realize the online transmission of several target wafers, film growth, resistivity detection, wafer classification and placement and other fully closed operations in the two chambers without breaking the chamber vacuum, without the need for intermediate shutdown and vacuum breaking operation, and can meet the requirements of online detection of the thin film resistivity on each wafer, and can timely feed back the data to the background terminal. After the background terminal adjusts the data, the corresponding process parameters can be modified again to realize process modification, shorten the process exploration time, reduce the vacuum pumping time, and effectively improve the process research and development efficiency of high-quality a-Ta thin films and the production efficiency of high-quality tantalum thin films; storing new wafers in a vacuum environment also ensures that the wafers are free from contamination, thereby improving the quality of tantalum thin films. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the following is a brief introduction to the drawings required for use in the embodiment:

[0019] Figure 1 It is a schematic structural diagram of a specific embodiment of a tantalum film preparation device capable of online resistivity detection according to the utility model;

[0020] Figure 2 for Figure 1 A front view of

[0021] Figure 3 for Figure 1 A schematic diagram of the structure of the first sample carrier;

[0022] Figure 4 for Figure 1 Schematic diagram of the structure of the wafer storage rack.

[0023] Description of reference numerals: 1-first chamber 1; 11-first vacuum device 11; 12-first vacuum gauge 12; 13-first sample carrier 13; 14-sample inlet and outlet door 14; 15-transport mechanism 15; 16-resistivity detection device 16; 17-wafer storage rack 17; 18-wafer collection rack 18;

[0024] 2-second chamber 2; 21-second vacuum device 21; 22-second vacuum gauge 22; 23-second sample carrier 23; 24-magnetron sputtering gun device 24; 25-crystal oscillator device 25; 26-return mechanism 26;

[0025] 3 - transport channel 3; 4 - gate valve 4; 5 - target wafer 5.

[0026] 131 - lifting platform 131; 132 - carrying frame 132; 133 - lifting mechanism 133;

[0027] 151-manipulator; 152-U-shaped fork 152;

[0028] 171 - sidewall 171, 172 - storage space 172;

[0029] 261 - conveying rod 261 ; 262 - front fork 262 . DETAILED DESCRIPTION

[0030] In order to make the technical purpose, technical solution and beneficial effects of the utility model clearer, the technical solution of the utility model is further described below in conjunction with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model, that is, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings can be arranged and designed in various different configurations.

[0031] The specific embodiment of the tantalum film preparation device capable of online resistivity detection of the utility model is as follows: Figures 1 to 4 As shown, the preparation device includes two chambers, namely a first chamber 1 and a second chamber 2. The two chambers are arranged side by side and spaced apart, and a sample delivery channel 3 is also connected between the first chamber 1. The sample delivery channel 3 is provided with a valve for controlling the isolation and connection between the first chamber 1 and the second chamber 2. In this embodiment, the valve is a gate valve 4, which can block the sample delivery channel 3 as a whole to isolate the vacuum between the two chambers.

[0032] For the first chamber 1, the front side is provided with a sample entry and exit door 14 for the operator to place the wafer into the first chamber 1 or take it out from the first chamber 1; the rear side of the first chamber 1 is connected to a first vacuum device 11 for evacuating and releasing the vacuum in the first chamber 1, and a first vacuum gauge 12 is also connected to the rear side of the first chamber 1 for measuring the vacuum degree in the first chamber 1.

[0033] A wafer storage rack 17 is provided on one side of the first chamber 1 near the sample inlet and outlet door 14. The wafer storage rack 17 has a storage space 172 for multi-layer storage. It adopts a U-shaped inverted chamber structure. A plurality of ribs 171 are evenly distributed at intervals on the inner walls on the left and right sides. The space between two adjacent ribs 171 constitutes a storage space 172 for placing target wafers. A target wafer 5 is arranged in each layer of storage space 172. The wafer storage rack 17 is used to stack multiple target wafers 5 at intervals. A wafer collection rack 18 is provided on the other side of the first chamber 1 near the sample inlet and outlet door 14. The wafer collection rack 18 is used to collect and place target wafers 5 that have completed thin film growth. The structure of the wafer collection rack 18 is basically the same as that of the wafer storage rack 17.

[0034] A first through port connected to the second chamber 2 is arranged on the right side of the first chamber 1, and a first sample carrier 13 is arranged on the left side of the first through port. The first sample carrier 13 includes a circular carrier frame 132, and the carrier frame 132 is used to support the wafer. A lifting platform 131 is movably installed at the center of the carrier frame 132. The bottom upper and lower guides of the lifting platform 131 are equipped with a lifting mechanism 133, which is used to drive the lifting platform 131 to move up and down. The lifting platform moves downward during the up and down movement to lower the lifting surface to the avoidance position below the upper end surface of the carrier, and also moves upward to lift the wafer to the pick-up and place position above the output end of the conveying mechanism and the return mechanism. During the up and down movement of the lifting platform, the target wafer is received from the conveying mechanism and the return mechanism, and the target wafer is placed downward on the carrier frame 132; or the target wafer is lifted upward and placed at the output end of the conveying mechanism and the return mechanism to achieve horizontal transportation of the target wafer.

[0035] A resistivity detection device 16 is provided at the inner rear side of the first chamber 1, and the resistivity detection device 16 is used to detect the resistivity of the thin film on the surface of the wafer, so as to analyze whether the phase of the thin film is a-Ta or β-Ta phase. In the present embodiment, the resistivity detection device 16 is a four-probe block resistance measuring instrument, and its structure and measurement principle are all existing technologies and are not described in detail.

[0036] A conveying mechanism 15 is provided at the middle position inside the first chamber 1, and a first sample carrier 13, a wafer storage rack 17, a wafer collecting part and a resistivity detection device 16 are arranged around the conveying mechanism 15. The conveying mechanism 15 is a wafer handling robot. The structure and working principle of the robot are consistent with the prior art. It includes a main arm and at least two support arms 151 connected to the main arm and hingedly assembled with each other. The support arms 151 rotate around the main arm and rotate relative to each other. Each rotation axis extends in the up and down direction. A U-shaped fork 152 is arranged at the tail end of the support arm 151 at the final end. The U-shaped fork 152 can be supported under the wafer and inserted into the wafer storage rack 17, the wafer collecting rack 18 and the resistivity testing device to realize the reciprocating movement and conveyance of the wafer at various positions.

[0037] The second chamber 2 has a second vacuum device 21 connected to its rear side for evacuating and releasing the vacuum in the second chamber 2 . Meanwhile, a second vacuum gauge 22 is also connected to the rear side of the second chamber 2 for measuring the vacuum degree in the second chamber 2 .

[0038] A second through port is provided on the right side inside the vacuum chamber, and a second sample carrier 23 is provided on the right side of the second through port. The structure of the second Yangping carrier is consistent with that of the first sample carrier 13 and is used to carry the target wafer 5 .

[0039] A magnetron sputtering gun device 24 is also provided inside the second chamber 2 for sputtering and depositing a Ta film toward the wafer, and a crystal oscillator device 25 is also provided inside the second chamber 2 for detecting the thickness of the tantalum film so as to observe the growth degree of the film. The magnetron sputtering chamber device and the crystal oscillator device 25 are conventional devices in the art and will not be described in detail.

[0040] A return mechanism 26 is installed on the right side guide inside the second chamber 2. The output end of the return mechanism 26 is consistent with the output end of the wafer handling robot. It has a front fork 262 and a conveying rod 261 connected to the right side of the front fork 262. The front fork 262 is used to extend to the peripheral side of the second sample carrier 23 and is located at the bottom of the wafer. Through the lifting mechanism 133 configured on the second sample carrier 23, the target wafer 5 is returned to the front fork 262 and avoids the left and right conveying paths of the front fork 262 and the conveying rod 261.

[0041] At the same time, a control host is connected to the rear side of the two chambers to control the automatic operation of the entire system.

[0042] During the actual working process, the sample inlet and outlet door 14 is first opened, and multiple target wafers 5 are placed on the wafer storage rack 17 in sequence, and then the sample inlet and outlet door 14 is closed, the first vacuum device 11 of the first chamber 1 and the second vacuum device 21 of the second chamber 2 are started, the insides of the two chambers are simultaneously vacuumed, and the value of the first vacuum gauge 12 in the first chamber 1 is less than 1.0E-6torr; the output end of the manipulator is controlled to be inserted into the wafer storage rack 17, and the single target wafer 5 is removed from the wafer storage rack 17, and at the same time the first sample carrier 13 falls back to avoid the conveying path of the manipulator The robot extends to the right and extends into the second chamber 2, and the second sample carrier 23 in the second chamber 2 falls back. After the U-shaped fork 152 of the robot moves into place, the second sample carrier 23 rises and passes through the U-shaped fork 152 of the robot to lift the target wafer, and then the robot retracts into the first chamber 1; then the gate valve 4 is opened to separate the first chamber 1 and the second chamber 2, and then the second chamber 2 is continuously evacuated. When the value of the second vacuum gauge 22 reaches a range less than about 5.0E-8torr, the vacuum degree inside the second chamber 2 meets the requirements of magnetron sputtering; at the The magnetron sputtering gun device 24 is started in the second chamber 2 to start growing a tantalum film on the surface of the target wafer 5. When the thickness of the tantalum film reaches the target thickness set by the crystal oscillator device 25, the magnetron sputtering gun device 24 is stopped, and the vacuum degrees of the first chamber 1 and the second chamber 2 are kept basically the same. Then, the gate valve 4 is opened, and the front fork 262 of the return mechanism 26 extends to the second sample carrier 23 and props up the wafer. The second sample carrier 23 falls back, and the return mechanism 26 enters the first chamber 1 through the sample delivery channel 3 and places the target wafer 5 on the first sample carrier 13; then the gate is closed. Valve 4, transfer the target wafer 5 to the resistivity testing device through the robot, test the block resistance of the tantalum film, calculate the resistivity of the tantalum film, and determine whether it is an a-Ta film based on the resistivity. If the resistivity is less than 70μΩ·cm, the target wafer 5 is transported to the wafer storage rack 17 through the robot. If the resistivity is greater than 70μΩ·cm, the target wafer 5 is transferred to the original position of the wafer storage rack 17 through the robot, and a new wafer is taken from the wafer storage rack 17. Repeat the above operation, send the sample to the second chamber 2, adjust the process parameters for growth, and repeat the above steps.

[0043] During the above operation, the transportation, magnetron sputtering, resistivity detection, etc. of each target wafer 5 are all carried out in the closed space composed of the first chamber 1 and the second chamber 2. There is no need to break the vacuum of the chamber, nor to take out the target wafer 5. The overall process has a high degree of automation, which greatly improves the process research and development efficiency of high-quality a-Ta films and the production efficiency of high-quality tantalum films.

[0044] Of course, in other embodiments, the target wafer 5 may be transported and carried by a robot or transmission mechanism of the same type, without any specific limitation.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate but not to limit the technical solutions of the present invention, and any equivalent substitutions of the present invention and any modifications or partial substitutions that do not depart from the spirit and scope of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A tantalum thin film preparation device capable of online resistivity detection, characterized in that: The invention comprises two chambers, both of which are equipped with a vacuum pump, and a sample delivery channel between the two chambers, wherein a valve for controlling the isolation and connection of the two chambers is arranged in the sample delivery channel, and the two chambers are defined as a first chamber and a second chamber respectively, and the first chamber has a sample inlet and outlet door, and the first chamber is provided with a wafer storage rack for centrally storing a plurality of target wafers, a wafer collection part for collecting target wafers after thin film growth, a first sample carrying platform for carrying a single target wafer, and a resistivity detection device for detecting the resistivity of the thin film, and a delivery channel is also arranged in the first chamber. A conveying mechanism, the output end of which is switched and moved between the wafer storage rack, the wafer collection part, the sample conveying channel and the resistivity detection device to convey the single target wafer between various positions; the second chamber is provided with a second sample carrier for carrying the target wafer, a magnetron sputtering gun device for sputtering and depositing a Ta film, and a crystal oscillator device for real-time detection of the thickness of the thin film growth, and also includes a feedback mechanism, the output end of which is used to move back and forth between the first sample carrier and the second sample carrier to transfer the target wafer between the first chamber and the second chamber.

2. The tantalum thin film preparation device capable of online resistivity detection according to claim 1, characterized in that: The wafer collecting part and the wafer storage rack are arranged on the peripheral side of the sample inlet and outlet door in the first chamber, the conveying mechanism is arranged at the center of the first chamber, and the resistivity detection device is arranged on the side facing away from the sample inlet and outlet door.

3. The tantalum thin film preparation device capable of online resistivity detection according to claim 2, characterized in that: The first sample carrier platform includes a lifting platform and a lifting mechanism connected to the bottom of the lifting platform. The outer side of the lifting platform is surrounded by a carrier frame. The lifting platform moves downward during the up and down movements to lower the lifting surface to an avoidance position below the upper end surface of the carrier platform. It also moves upward to lift the wafer to a pick-up and place position above the output end of the conveying mechanism and the return mechanism.

4. The tantalum thin film preparation device capable of online resistivity detection according to claim 3 is characterized in that: The conveying mechanism includes a wafer handling robot, which includes a main arm and a support arm connected to the main arm. There are more than two support arms, which are hinged and connected in series with each other. The swing axis of the support arm is consistent with the swing axis of the main arm. The tail end of the support arm is connected to a fork for supporting the bottom side of the target wafer.

5. The tantalum thin film preparation device capable of online resistivity detection according to claim 3, characterized in that: The return mechanism comprises a conveying rod which is guided and assembled in the second chamber, and the tail end of the conveying rod is provided with a front fork which is used for hanging to the bottom of the wafer.

6. The tantalum thin film preparation device capable of online resistivity detection according to claim 2, characterized in that: The wafer collecting unit comprises a wafer collecting rack arranged in the first chamber, the wafer collecting rack is used to place target wafers with qualified film resistivity, and target wafers with unqualified resistivity can be put back on the wafer storage rack.

7. The tantalum thin film preparation device capable of online resistivity detection according to any one of claims 1 to 6, characterized in that: The wafer storage rack has two vertical plates, and the opposite side walls of the vertical plates are respectively provided with ribs extending relatively to each other. There are a plurality of ribs, which are evenly spaced along the upper and lower directions of the corresponding side walls, and the space between two adjacent ribs constitutes a storage space for placing the target wafer.

8. The tantalum thin film preparation device capable of online resistivity detection according to claim 7, characterized in that: The wafer storage rack comprises a frame body with an inverted U-shaped cross section, and vertical arms on the left and right sides of the frame body constitute the vertical plates.

9. The tantalum thin film preparation device capable of online resistivity detection according to any one of claims 1 to 6, characterized in that: The valve is a gate valve.

10. The tantalum thin film preparation device capable of online resistivity detection according to any one of claims 1 to 6, characterized in that: The resistivity detection device is a sheet resistance testing device and the sheet resistance measuring instrument is a sheet resistance measuring instrument.

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