PVD film formation system and PVD film formation method

Abstract

The invention discloses a PVD film forming system and a PVD film forming method. The PVD film forming system comprises: a PVD device, which is used for receiving a carrier plate carrying a silicon wafer and forming an ITO film on the silicon wafer; the silicon wafer transfer device is used for transferring the silicon wafer plated with the ITO film from the carrier plate to a flower basket; the ultrasonic washing equipment is used for receiving the flower basket which is provided by the silicon wafer transfer device and carries the silicon wafer, and comprises a water tank, an ultrasonic oscillator for generating ultrasonic waves for cleaning and a washing module; the water washing module is used for introducing bubbling nitrogen into the water tank to clean the silicon wafer for a preset duration so as to enable adhesive dust on the surface of the silicon wafer to fall off; and the drying equipment is used for drying the silicon wafers which are loaded in the flower basket and cleaned by the ultrasonic washing equipment. Dust generated in the PVD film forming process can be effectively removed, so that the service life of a screen printing plate in the silk-screen printing technology is effectively prolonged, and the battery conversion efficiency is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic manufacturing, and in particular to a PVD film forming system and a PVD film forming method. Background Art

[0002] Indium Tin Oxides (ITO) of heterojunction solar cells is formed by sputtering through physical vapor deposition (PVD) process. In order to speed up the ITO film formation speed, the PVD process usually uses a strong magnetic field with a strength of 500-1200 Gauss. When the ITO film is formed on the surface of the cell, adhesive dust is easily generated. This dust will affect the service life of the steel screen, nickel screen and / or polyimide PI screen in the subsequent screen printing process. At the same time, the dust itself will also have an adverse effect on the conversion efficiency of the battery itself.

[0003] Therefore, how to provide a PVD film forming system and a PVD film forming method to effectively remove the dust generated during the PVD film forming process and effectively improve the screen plate life and battery conversion efficiency in the screen printing process has become a technical problem that needs to be urgently solved in the industry. Summary of the invention

[0004] In view of the above problems in the prior art, the present invention proposes a PVD film forming system, comprising:

[0005] A PVD device, which is used to receive a carrier board carrying a silicon wafer and form an ITO film on the silicon wafer;

[0006] A silicon wafer transfer device, which is used to transfer the silicon wafer coated with the ITO film from the carrier plate to the flower basket;

[0007] an ultrasonic water washing device, which is used to receive the basket carrying the silicon wafers provided by the silicon wafer transfer device, and comprises a water tank, an ultrasonic oscillator for generating ultrasonic waves for cleaning, and a water washing module, wherein the water washing module is used to introduce bubbling nitrogen into the water tank to clean the silicon wafers for a predetermined time to remove dust adherent to the surface of the silicon wafers; and

[0008] The drying device is used to dry the silicon wafers loaded in the flower basket and cleaned by the ultrasonic water washing device.

[0009] In one embodiment, the PVD equipment is a strong magnetic PVD equipment, and its magnetic field strength is 500-1200 Gauss.

[0010] In one embodiment, the water tank of the ultrasonic water washing equipment is sized to accommodate two to eight flower baskets, a perforated mesh plate is provided at the bottom of the water tank, and the water washing module controls the circulation of ultrapure water and nitrogen bubbling through the perforated mesh plate.

[0011] In one embodiment, the water washing module controls the temperature of the circulating ultrapure water to 25-50 degrees Celsius, and the resistivity of the ultrapure water added to the water tank is controlled to be above 17MΩ.cm.

[0012] In one embodiment, the drying equipment includes a drying trough body, the size of which can accommodate two to eight flower baskets, the side walls of the drying trough body are provided with blowing holes, and the bottom wall is provided with a circulating return air port. The drying equipment uses its fan to circulate air at the circulating return air port to dry the silicon wafers in the flower basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

[0013] The present invention also provides a PVD film forming method, comprising the following steps:

[0014] Step 1, placing the silicon wafer on a carrier for PVD film formation;

[0015] Step 2: Send the carrier board carrying the silicon wafer to the PVD equipment to form an ITO film;

[0016] Step 3, transferring the carrier carrying the silicon wafer coated with the ITO film out of the PVD device;

[0017] Step 4, transferring the silicon wafer from the carrier plate to the flower basket;

[0018] Step 5, sending the basket loaded with silicon wafers to an ultrasonic washing device;

[0019] Step 6, turning on the ultrasonic oscillator of the ultrasonic water washing device to generate ultrasonic waves for cleaning, and introducing bubbling nitrogen into the ultrasonic water washing device to clean the silicon wafer for a predetermined time to remove dust adherent to the surface of the silicon wafer; and

[0020] Step seven, sending the basket loaded with silicon wafers to a drying device for drying.

[0021] In one embodiment, the PVD equipment is a strong magnetic PVD equipment, and its magnetic field strength is 500-1200 Gauss.

[0022] In one embodiment, the ultrasonic water washing equipment in step five includes a water tank, the ultrasonic oscillator and a water washing module. The size of the water tank is set to accommodate two to eight flower baskets. A perforated mesh plate is provided at the bottom of the water tank. The water washing module controls the circulation of ultrapure water and nitrogen bubbling through the perforated mesh plate.

[0023] In one embodiment, the temperature of the circulating ultrapure water in step five is controlled at 25-50 degrees Celsius, and the resistivity of the ultrapure water added to the water tank is controlled at above 17 MΩ.cm.

[0024] In one embodiment, the drying equipment in step seven includes a drying tank body, the size of which can accommodate two to eight flower baskets, the side walls of the drying tank body are provided with blowing holes, and the bottom wall is provided with a circulating return air port. The drying equipment uses its fan to circulate air at the circulating return air port to dry the silicon wafers in the flower basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

[0025] Compared with the prior art in which the silicon wafer is not subjected to ultrasonic nitrogen bubbling water washing after PVD film formation, which easily leads to dust affecting the service life of the screen in the screen printing process, the PVD film forming system and PVD film forming method of the present invention first place the silicon wafer in a carrier for PVD film formation, then send the carrier carrying the silicon wafer to the PVD device to form an ITO film, then send the carrier carrying the silicon wafer coated with the ITO film out of the PVD device, then transfer the silicon wafer from the carrier to a basket, then send the basket loaded with the silicon wafer to an ultrasonic water washing device, then turn on the ultrasonic oscillator of the ultrasonic water washing device to generate ultrasonic waves for cleaning, and introduce bubbling nitrogen into the ultrasonic water washing device, clean the silicon wafer for a predetermined time to make the dust on the surface of the silicon wafer fall off, and finally send the basket loaded with the silicon wafer to a drying device for drying. The present invention can effectively remove the dust generated in the PVD film forming process, thereby effectively improving the screen life and battery conversion efficiency in the screen printing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0027] Figure 1 A schematic diagram of the composition structure of a PVD film forming system embodiment of the present invention; and

[0028] Figure 2 It is a schematic flow chart of an embodiment of the PVD film forming method of the present invention. DETAILED DESCRIPTION

[0029] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0032] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0033] See also Figure 1 , which is a schematic diagram of the composition structure of the PVD film forming system embodiment of the present invention. Figure 1As shown, the PVD film forming system of the present invention includes a PVD device 1, a silicon wafer transfer device 2, an ultrasonic water washing device 3 and a drying device 4. The PVD device 1 is used to receive a carrier board carrying silicon wafers and form an ITO film on the silicon wafers. The PVD device is a strong magnetic PVD device with a magnetic field strength of 500-1200 Gauss. The silicon wafer transfer device 2 is used to transfer the silicon wafers coated with the ITO film from the carrier board to the basket, the ultrasonic water washing device 3 is used to receive the basket carrying the silicon wafers provided by the silicon wafer transfer device 2, and the drying device 4 is used to dry the silicon wafers loaded in the basket and cleaned by the ultrasonic water washing device 3. The silicon wafer transfer device 2 is usually a fully automated transfer device.

[0034] like Figure 1 As shown, the ultrasonic water washing device 3 includes a water tank 30, an ultrasonic oscillator 32 and a water washing module 34. The ultrasonic oscillator 32 is used to generate ultrasonic waves for cleaning. The water washing module 34 is used to introduce bubbling nitrogen into the water tank 30 to clean the silicon wafer for a predetermined time to remove the adhesive dust on the surface of the silicon wafer. The predetermined time can be 60-120 seconds. The water tank 30 of the ultrasonic water washing device 3 is sized to accommodate two to eight flower baskets. A perforated mesh plate 36 is provided at the bottom of the water tank so that the water washing module 34 can circulate ultrapure water and bubble nitrogen. The ultrasonic oscillator 32 is arranged in the water tank 30. The flower basket can carry 232 silicon wafers. The length, width and height of the flower basket are 700mm, 290mm and 270mm respectively. The flower basket can also be the commonly used specifications and sizes for wet cleaning in the industry.

[0035] The water washing module 34 controls the temperature of the circulating ultrapure water to 25-50 degrees Celsius, and controls the resistivity of the ultrapure water added to the water tank to be above 17 MΩ.cm.

[0036] like Figure 1 As shown, the drying device 4 includes a drying tank body 40, the size of which can accommodate two to eight flower baskets, the side wall of the drying tank body 40 is provided with a blowing hole (not shown), and the bottom wall is provided with a circulating return air port (not shown). The drying device uses its fan (not shown) to circulate air at the circulating return air port to dry the silicon wafers in the flower basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

[0037] See also Figure 2 , which is a schematic flow chart of an embodiment of the PVD film forming method of the present invention. Figure 2 As shown, the PVD film forming method S20 of the present invention first performs step S200 to place a silicon wafer on a carrier for PVD film forming.

[0038] The PVD film forming method S20 then proceeds to step S210, sending the carrier carrying the silicon wafer to a PVD device to form an ITO film. In this embodiment, the PVD device is a strong magnetic PVD device with a magnetic field strength of 500-1200 Gauss.

[0039] The PVD film forming method S20 then proceeds to step S220, where the carrier carrying the silicon wafer coated with the ITO film is transferred out of the PVD device. In this embodiment, the carrier can be transferred out of the PVD device by a roller assembly.

[0040] The PVD film forming method S20 then proceeds to step S230, transferring the silicon wafers from the carrier plate to a basket. The basket can be a commercially available common wet cleaning basket, and each basket can carry 232 silicon wafers.

[0041] The PVD film forming method S20 then proceeds to step S240, where the basket loaded with the silicon wafer is sent to an ultrasonic water washing device. In step S240 of this embodiment, the water tank size of the ultrasonic water washing device is set to accommodate two to eight horizontally placed flower baskets, and a mesh plate with holes is provided at the bottom of the water tank to facilitate ultrapure water circulation and nitrogen bubbling, and an ultrasonic oscillator for generating ultrasonic waves for cleaning is provided in the water tank. The ultrapure water circulation and nitrogen bubbling during the cleaning process can improve the dust removal effect on the surface of the blue film silicon wafer coated with the ITO film.

[0042] The PVD film forming method S20 then proceeds to step S250, turning on the ultrasonic oscillator of the ultrasonic water washing device to generate ultrasonic waves for cleaning, and introducing bubbling nitrogen into the ultrasonic water washing device to clean the silicon wafer for a predetermined time to remove the dust adherent to the surface of the silicon wafer. In step S250 of this embodiment, the temperature of the circulating ultrapure water is controlled at 25-50 degrees Celsius, and the resistivity of the ultrapure water added to the water tank is controlled to be above 17MΩ.cm.

[0043] The PVD film forming method S20 finally performs step S260, sending the basket loaded with silicon wafers to a drying device for drying. In this embodiment, the drying device includes a drying tank body, the size of which can accommodate two to eight baskets, the side wall of the drying tank body is provided with a blowing hole, and the bottom wall thereof is provided with a circulating return air port. The drying device uses its fan to circulate air at the circulating return air port to dry the silicon wafers in the basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

[0044] In other embodiments, the drying device may be a spin-drying device, which separates and removes the water from the washing in step S250 by centrifugal force.

[0045] Compared with the prior art, under the same production capacity, the PVD film forming method of the present invention can reduce screen damage caused by dust, increase the service life of the screen from 50,000 printing pieces to 100,000 pieces, and increase the conversion efficiency of the battery by at least 0.1% on average.

[0046] In summary, the PVD film forming system and PVD film forming method of the present invention first place the silicon wafer in the PVD film forming carrier, then send the carrier carrying the silicon wafer to the PVD device to form an ITO film, then send the carrier carrying the silicon wafer coated with the ITO film out of the PVD device, then transfer the silicon wafer from the carrier to the basket, then send the basket carrying the silicon wafer to the ultrasonic water washing device, then turn on the ultrasonic oscillator of the ultrasonic water washing device to generate ultrasonic waves for cleaning, and introduce bubbling nitrogen into the ultrasonic water washing device, clean the silicon wafer for a predetermined time to make the dust adherent on the surface of the silicon wafer fall off, and finally send the basket carrying the silicon wafer to the drying device for drying. The present invention can effectively remove the dust generated in the PVD film forming process, thereby effectively improving the screen life and battery conversion efficiency in the screen printing process.

[0047] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the universal principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein. The above embodiments are provided to persons familiar with the art to implement or use the present invention, and persons familiar with the art may make various modifications or changes to the above embodiments without departing from the inventive concept of the present invention, and thus the scope of protection of the present invention is not limited by the above embodiments, but should be the maximum scope of the innovative features mentioned in the claims.

Claims

1. A PVD film forming system, characterized in that: include: A PVD device, which is used to receive a carrier board carrying a silicon wafer and form an ITO film on the silicon wafer; A silicon wafer transfer device, which is used to transfer the silicon wafer coated with the ITO film from the carrier plate to the flower basket; An ultrasonic water washing device, which is used to receive the basket carrying the silicon wafers provided by the silicon wafer transfer device, and comprises a water tank, an ultrasonic oscillator for generating ultrasonic waves for cleaning, and a water washing module, wherein the water washing module is used to introduce bubbling nitrogen into the water tank to clean the silicon wafers for a predetermined time to remove dust adherent to the surface of the silicon wafers; as well as The drying device is used to dry the silicon wafers loaded in the flower basket and cleaned by the ultrasonic water washing device.

2. The PVD film forming system according to claim 1, characterized in that: The PVD equipment is a strong magnetic PVD equipment, and its magnetic field strength is 500-1200 Gauss.

3. The PVD film forming system according to claim 1, characterized in that: The water tank size of the ultrasonic water washing equipment is set to accommodate two to eight flower baskets, and a perforated mesh plate is arranged at the bottom of the water tank. The water washing module controls the circulation of ultrapure water and nitrogen bubbling through the perforated mesh plate.

4. The PVD film forming system according to claim 3, characterized in that: The water washing module controls the temperature of the circulating ultrapure water at 25-50 degrees Celsius, and the resistivity of the ultrapure water added to the water tank is controlled to be above 17MΩ.cm.

5. The PVD film forming system according to claim 1, characterized in that: The drying equipment comprises a drying trough body, the size of which can accommodate two to eight flower baskets, the side wall of which is provided with a blowing hole, and the bottom wall of which is provided with a circulating return air port, and the drying equipment utilizes its fan to circulate air through the circulating return air port to dry the silicon wafers in the flower basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

6. A PVD film forming method, characterized in that: The following steps are involved: Step 1, placing the silicon wafer on a carrier for PVD film formation; Step 2: Send the carrier board carrying the silicon wafer to the PVD equipment to form an ITO film; Step 3, transferring the carrier carrying the silicon wafer coated with the ITO film out of the PVD device; Step 4, transferring the silicon wafer from the carrier plate to the flower basket; Step 5, sending the basket loaded with silicon wafers to an ultrasonic washing device; Step 6, turning on the ultrasonic oscillator of the ultrasonic water washing device to generate ultrasonic waves for cleaning, and introducing bubbling nitrogen into the ultrasonic water washing device to clean the silicon wafer for a predetermined time to remove dust adherent to the surface of the silicon wafer; as well as Step seven, sending the basket loaded with silicon wafers to a drying device for drying.

7. The PVD film forming method according to claim 6, characterized in that: The PVD equipment is a strong magnetic PVD equipment, and its magnetic field strength is 500-1200 Gauss.

8. The PVD film forming method according to claim 6, characterized in that: The ultrasonic water washing equipment in step five includes a water tank, the ultrasonic oscillator and a water washing module. The size of the water tank is set to accommodate two to eight flower baskets. A perforated mesh plate is set at the bottom of the water tank. The water washing module controls the circulation of ultrapure water and nitrogen bubbling through the perforated mesh plate.

9. The PVD film forming method according to claim 8, characterized in that: In step 5, the temperature of the circulating ultrapure water is controlled at 25-50 degrees Celsius, and the resistivity of the ultrapure water added to the water tank is controlled at above 17 MΩ.cm.

10. The PVD film forming method according to claim 6, characterized in that: The drying equipment in step seven includes a drying tank body, the size of which can accommodate two to eight flower baskets, the side walls of the drying tank body are provided with blowing holes, and the bottom wall is provided with a circulating return air port. The drying equipment uses its fan to circulate air at the circulating return air port to dry the silicon wafers in the flower basket, and the blowing temperature is controlled at 25-50 degrees Celsius.

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