JP6816132B2 - Wafer plate and mask equipment for substrate manufacturing - Google Patents

Description

The present application relates to vacuum processing systems such as systems used in the manufacture of solar cells, flat panel displays, touch screens and the like.

Various systems for manufacturing semiconductor ICs, solar cells, touch screens and the like are known in the art. The steps in these systems are performed in vacuum and include, for example, physical vapor deposition (PVD), chemical vapor deposition (CVD), ion implantation, etching and the like. There are two basic methods used in such systems: single substrate processing or batch processing. In single wafer processing, only a single substrate is present in the chamber during processing. In batch processing, multiple substrates are present in the chamber during processing. Single substrate processing allows a high level of control between the processing inside the chamber and the membrane or structure formed on the substrate, but with relatively low throughput. On the other hand, batch processing has less control over the processing conditions and the resulting film or structure, but has much higher throughput.

Batch processing such as processing used in manufacturing systems such as solar cells and touch panels is generally performed by transporting and manufacturing substrates arranged in a two-dimensional array of n × m substrates. As an example, the PECVD system for solar cell manufacturing developed by Roth & Rau uses a tray of 5x5 wafers with a throughput of 1200 wafers / hour reported in 2005. However, other systems use trays with 6x6, 7x7, 8x8, and even more 2D array wafers. The use of trays for 2D array wafers increases throughput, but complicates the handling and loading / unloading operations of such large trays.

In some steps, it is necessary to apply a bias such as RF or DC potential to the substrate to be processed. However, it is difficult to apply a bias because the batch system uses trays that move with the substrate.

Further, while some steps are performed while holding the substrate horizontally, it may be advantageous for some steps to hold the substrate vertically. However, loading and unloading the board vertically is more complicated than loading and unloading the board horizontally.

Some steps require the use of masks to shield parts of the substrate from certain manufacturing processes. For example, to prevent battery shunting, masks may be used to form contacts or exclude edges. That is, when the battery has contacts on the front and back sides, the material for forming the contacts may be deposited on the edge of the wafer to shunt the front and back contacts. Therefore, it is desirable to exclude the edges of the battery with a mask, at least when manufacturing front or back contacts.

In another aspect, when manufacturing a silicon solar cell, it is desirable to deposit a blanket metal on the back surface to function as a light reflector or an electrical conductor. The metal is generally aluminum, but the blanket metal may be any metal used for multiple reasons such as cost, conductivity, solderability and the like. The deposited film thickness may be very thin, for example, about 10 nm, and may be very thick, for example, from 2 μm to 3 μm. However, wraparound of the blanket metal around the edge of the silicon wafer must be prevented as it creates a resistive connection between the front and back surfaces of the solar cell, i.e. a shunt. An exclusion region is provided on the back edge of the wafer to prevent this connection. The typical size of the exclusion region is less than 2 mm wide, but it is preferable to make the exclusion region as thin as possible.

One of the methods for providing the exclusion area is by using a mask, but there are many problems in using the mask. Due to the high competitiveness of the solar industry, masks need to be manufactured at extremely low prices. In addition, due to the high throughput of solar manufacturing equipment (generally 1500 to 2500 cells / hour), the use of masks requires speed and convenience in mass production. In addition, since the mask is used to prevent film deposition on specific parts of the wafer, it must be able to absorb and contain the piled up deposits. In addition, since the film deposition is carried out at high temperatures, the mask can function properly at high temperatures, for example up to 350 ° C., and adapt to the warpage of the substrate due to thermal stress while accurately maintaining the width of the exclusion region. Must be.

The following outline is incorporated to gain a basic understanding of some aspects and features of the invention. This overview is not a broad overview of the invention and is not intended by itself to specifically identify important or essential elements of the invention or to define the scope of the invention. As a prelude to a more detailed embodiment described below, the sole purpose is to present some concepts of the invention in a simplified form.

Embodiments of the present invention are modules that allow the use of various processes and process steps, and are versatile, suitable for the manufacture of various devices, including, for example, solar cells, flat panel displays, touch screens, and the like. Provide system configuration. In addition, the system can handle various types and sizes of substrates by simply changing the susceptors used, without reconfiguration.

This system configuration makes it possible to handle substrates such as load and unload in an atmospheric environment, which is separate from vacuum processing. Also, various embodiments allow manual load / unload when the automatic operation is idle or absent, i.e. the system can be applied without load / unload automation. In a vacuum environment, the system allows static processing or pass-by processing of the substrate. In certain embodiments, actuating valves are utilized to provide vacuum separation between the processing chambers. In various embodiments, electrostatic chucks are provided on the substrate to allow efficient cooling and prevent accidental movement of the substrate. In other embodiments, the mechanical chuck is provided, for example, using a spring-loaded clip with a relief device for loading / unloading the substrate. Further, in various embodiments, for example, a substrate bias using an RF or DC bias power supply, or a substrate floating is also possible.

In various embodiments, handling with a line array carrier can simplify the handling of the substrate, but processing can be performed with an n × m two-dimensional array substrate by simultaneously processing a plurality of line array carriers. Will be. In other embodiments, the substrate is processed in the vertical direction, but is provided with a carrier that is loaded and unloaded when the substrate is handled horizontally.

Further, in the embodiment of the present invention, it is possible to process the substrate using a mask, which is carried out by using a dual mask device. The two-part mask system is configured to mask the substrate and is placed on top of an inner mask consisting of an inner mask consisting of a metal flat sheet with an aperture that exposes a portion of the wafer to be processed. Includes an outer mask that is thicker than the thickness of the inner mask, has an opening cut of a size and shape similar to the size and shape of the substrate, and is configured to mask the inner mask. The mask frame may be configured to support the inner mask and the outer mask so that the outer mask is sandwiched between the mask frame and the inner mask. In one embodiment, when a dual mask appliance is used for edge separation, the open cut of the inner mask has a size slightly smaller than that of the solar wafer, thus covering the periphery of the wafer when the inner mask is placed on the wafer. , The open cut of the outer mask is slightly larger than the open cut of the inner mask. The top frame carrier may be used to hold the inner mask and the outer mask and to fix the inner mask and the outer mask to the wafer susceptor.

A load / unload device that handles four rows of boards at the same time is provided. The load / unload device has a descending position and an ascending position, and is configured for vertical motion. In the lowered position, the instrument removes the row of treated substrates from one carrier, places the row of untreated substrates on an empty carrier, and installs the row of treated substrates on the substrate removal appliance. It is configured to do so and to retrieve the row of untreated substrates from the substrate transfer device at the same time. The board removing device and the board transferring device may be conveyor belts that move in the same direction or in opposite directions. In the ascending position, the instrument is configured to rotate 180 degrees.

In certain embodiments, a configuration is used in which the wafer plate is attached to the carrier from below, while the masking device is attached to the carrier from above. One of the wafer plates or masking fixtures can be attached to the carrier in a fixed orientation and the other can be realigned during loading of each unprocessed wafer. In an exemplary embodiment, the masking device is placed on the carrier in a fixed orientation. When the untreated wafer is loaded onto the wafer plate, the wafer plate is placed in a position below the carrier. A camera is then used to verify the alignment of the wafer with respect to the masking device. The wafer plate can then be moved and / or rotated to provide proper alignment with the masking instrument. When properly oriented, the wafer plate is raised and attached to the carrier, for example using a series of magnets. In one embodiment, since the wafer plate includes suction holes, a vacuum is applied to the suction holes during the alignment step to hold and press the wafer against the wafer plate.

The accompanying drawings which are incorporated in the present specification and constitute a part thereof exemplify the embodiment of the present invention, and play a role of explaining and illustrating the principle of the present invention together with the mode for carrying out the invention. The drawings are intended to diagrammatically show the main features of the exemplary embodiments. Also, it is not intended that the drawings present all the features of the actual embodiment or the relative sizes of the elements illustrated, and the drawings are not at an exact scale.

FIG. 1 shows an embodiment of a multi-board processing system in which the carrier supports the line array substrate, but the processing is performed on the two-dimensional array substrate, and FIG. 1A shows a system in which the carriers are in the horizontal direction during transportation and processing. 1B shows an embodiment in which the carriers are horizontal during transport and load / unload, but vertical during processing. FIG. 2 shows a multi-wafer carrier according to an embodiment, FIG. 2A shows a partial cross section, FIG. 2B shows an example of a carrier for processing a silicon wafer, and FIG. 2C shows a glass substrate. An example of a carrier for processing is shown. FIG. 3A is a plan view of the load / unload device according to the embodiment, FIG. 3B is a side view thereof, and FIG. 3C shows an embodiment of the substrate alignment device. FIG. 4 shows an embodiment of a vacuum processing chamber 400 that can be used with the systems of the present disclosure. FIG. 5 shows an embodiment of a mask and carrier assembly. 6A-6C show three embodiments showing how a vacuum chamber can be adapted to different processing sources of various sizes and configurations. 7A-7E show diagrams of multi-wafer carriers with dual masking appliances according to various embodiments. FIG. 8 is a cross section of the enlarged portion of the frame, the outer mask and the inner mask according to one embodiment, and FIG. 8A is a cross section of the enlarged portion of the frame, the outer mask and the inner mask according to another embodiment. .. FIG. 9 shows an embodiment of an outer mask in which an inner mask is fitted. FIG. 10 shows an embodiment of an inner mask used for edge separation. FIG. 11 shows an embodiment of a single wafer carrier. FIG. 12 shows a bottom view of an embodiment of the outer mask. FIG. 13 shows an embodiment of a top frame for supporting the inner mask and the outer mask. FIG. 14 shows an embodiment of an inner mask for forming a plurality of holes in a wafer. FIG. 15 shows an embodiment of a susceptor used with the mask of FIG. 16A-16D show embodiments in which the wafer plate is attached to the carrier from below while the dual mask is attached from above. FIG. 16E shows a double mask device according to an embodiment. FIG. 16F is a cross-sectional view of a part of the system according to the embodiment, and the enlarged portion is shown in the balloon. FIG. 16G shows a wafer plate according to another embodiment provided with a vacuum mesa and a peripheral buffer. FIG. 16H shows the upper part of the load and alignment stage according to the embodiment. FIG. 16I shows the upper part of the unload stage according to the embodiment.

The following detailed description provides examples with an emphasis on specific features and embodiments of the innovative processing systems described herein. In various embodiments disclosed, a system is provided for simultaneously processing a plurality of substrates, such as a semiconductor or glass substrate, inside a vacuum processing chamber, such as a plasma processing chamber. Although glass substrates such as those used for touch screens are generally not considered wafers, the reference examples for wafers in this disclosure are used for ease of understanding, and glass substrates are all such. It needs to be understood that it can be an alternative to the reference example of.

FIG. 1 is a plan view showing an embodiment of a multi-board processing system in which a transport carrier supports a line array substrate, but processing is performed on a two-dimensional array substrate. In system 100 shown in FIG. 1, the substrate is loaded and unloaded at the load / unload station 105, i.e. from the same side of the system. However, it should also be understood that the system can be designed so that the load station is on one side of the system and the unload station is on the other side of the system. In some embodiments, loading and / or unloading from the carrier of the substrate may be done manually, but in other embodiments, these one or two tasks are done automatically. ..

The substrate is loaded onto the carrier located at the load / unload station 105, which is conveyed from the carrier return station 110. Each carrier supports a line array substrate, i.e. two or more substrates arranged in a single row, in a direction perpendicular to the direction of movement within the system. The carrier moves from the load / unload station 105 to the buffer station 115 via the carrier return station 110. The carrier also stays at buffer station 115 until it is ready to accept the low vacuum load lock (LVLL) 120. In some embodiments described below, the buffer station also functions as a tilting station and is tilted 90 degrees so that the horizontal carriers take the vertical direction. In such an embodiment, the clip is used to hold the substrate in place when oriented vertically.

The valve 112 opens at an appropriate time and the carrier located at the buffer station 115 is conveyed to the LVLL 120. The valve 112 is then closed and the LVLL 120 is evacuated to a low vacuum level. The valve 113 is then opened and the carrier from the LVLL 120 is transferred into the high vacuum load lock (HVLL) 125. When the HVLL is pumped to vacuum level, the valve 114 opens and the carrier from the HVLL 125 is transferred into the processing chamber 130. The system may have any number of processing chambers 130 arranged linearly so that they are transferred from one chamber to the next via a valve located between each of the two processing chambers. Good. At the end of the final processing chamber is a valve that leads to a reverse load lock device, such as an inlet to the system, that is, first HVLL then LVLL. The carrier then exits the carrier return module 135 via valve 116. The carrier is returned from the return module 135 to the carrier return station 110 using, for example, a conveyor (not shown) located above or below the processing chamber 130.

As mentioned above, each carrier supports a linear array substrate, which simplifies the loading and unloading of the substrate and greatly facilitates the manufacture, handling and transport of the carriers. However, due to the high throughput of the system, each processing chamber 130 is configured to accommodate a plurality of sequentially arranged two-dimensional array substrates, i.e. arranged on two or more carriers, and process them simultaneously. .. In the particular embodiment of FIG. 1, for greater efficiency, the buffer stations 115, LVLL 120, and HVLL 125 are each configured to simultaneously accommodate the same number of carriers as are simultaneously accommodated in the processing chamber 130. To. For example, each carrier may support three glass substrates in a row, but each processing chamber is configured to process two carriers simultaneously to process a 3x2 2D array substrate.

In other embodiments, the load lock and buffer chamber are sized to handle multiple carriers, eg, two carriers, in order to increase pump / vent and pressure stabilization time. The buffer chamber is also used for carrier motion transitions, from one station-to-station motion to one of the continuous pass-by motions within the processing chamber. May be done. For example, if one processing chamber processes carriers in stationary mode while the next chamber processes in pass-by mode, the buffer chambers may be located between the two chambers. Carriers in the system create a continuous flow of carriers within the processing chamber or module, with each processing chamber / module passing through a process source (eg, heat source, PVD, etching, etc.) end-to-end. It may have 5 to 10 carriers that move continuously.

As shown in FIG. 1, a part of the system provided for substrate transport, loading and unloading is located in the atmospheric environment. On the other hand, all processing is performed in a vacuum environment. Transporting, loading and unloading in an atmospheric environment is much easier than in the case of vacuum.

FIG. 1A shows an embodiment of a system as shown in FIG. In FIG. 1A, the carrier 200 is held horizontally during transport and processing. The carrier is returned to the starting point via a linear conveyor 140 located above the processing chamber. The linear conveyor 140 may be a conveyor belt or a series of motorized wheels. As shown in FIG. 1A, each carrier 200 supports four substrates 220 arranged linearly in a row. Also, the top of the chamber 120 has been removed for explanatory purposes to reveal the six carrier sequences that are placed simultaneously. Therefore, according to this embodiment, each chamber simultaneously processes 24 substrates while each carrier supports 4 substrates.

FIG. 1B shows an embodiment in which the carriers are horizontal during transport and load / unload, but vertical during processing. The configuration of FIG. 1B is very similar to the configuration of FIG. 1A, except that the load lock and the processing chamber are vertically flipped to process the substrate in the vertical direction. The configuration of the load lock and the processing chamber can be similar in the embodiments of FIGS. 1A and 1B, except that they are mounted horizontally in FIG. 1A but vertically at their sides in FIG. 1B. Therefore, the buffer station 115 and the buffer station 145 at the other end of the system are modified to include a lifting device that orients the carrier 90 degrees, as shown by the buffer station 145.

FIG. 2 shows a line array carrier according to an embodiment that can be configured to process silicon wafers, glass substrates, and the like. As shown in FIG. 2, the configuration of the line array carrier according to the present embodiment is relatively simple and inexpensive. It should be understood that carriers can be configured for different numbers of substrates and substrate sizes by simply mounting different chucks on top of the carriers. It also needs to be understood that each processing chamber can simultaneously process a plurality of wafers on a plurality of carriers by being configured to accommodate several carriers at the same time.

The carrier 200 of FIG. 2 is composed of a simple frame 205 formed by two transport rails 225 and two ceramic bars 210. The ceramic bar 210 improves the insulation of the susceptor (not shown) attached therein from the rest of the chamber. At least one side of each ceramic bar 210 forms a fork mechanism 235 together with the transport rail 225, as shown in the balloon diagram. The cavity 245 is formed in the fork mechanism 235 to allow the ceramic bar 210 to move freely by thermal expansion (indicated by a bidirectional arrow) and to prevent pressure from being applied to the transport rail 225.

Magnetic drive bars 240 are provided on each of the transport rails 225 to allow carriers to be transported throughout the system. The magnetic drive bar is mounted on the magnetic wheel to carry the carrier. The drive bar 240 may be nickel-plated to improve the cleanliness of the system. This magnetic mechanism enables accurate transfer of carriers without slippage due to high acceleration. Further, by this magnetic mechanism, the carrier is attached to the wheel by magnetic force, and it is possible to cross a large gap almost like a cantilever, so that a large wheel space can be taken. In addition, since the carrier is magnetically attached to the wheel, this magnetic mechanism allows the carrier to be transported either vertically or horizontally.

The carrier contact assembly 250 is attached to the transport rail 225 and is connected to the chamber contact assembly 252 attached to the chamber (see blowout diagram). The chamber contact assembly has an insulating bar 260 in which a contact brush 262 is embedded. The contact assembly 250 comprises a conductive extension 251 (FIG. 2A) inserted between the insulating spring 264 and the insulating bar 260 and is pressed against the contact brush 262 to receive a bias potential from the connecting contact. The bias may be used, for example, for a substrate bias, a substrate chuck (for an electrostatic chuck), or the like. The bias may also be RF or DC (persistent or pulsed). The carrier contact assembly 250 may be provided on one or both sides of the carrier.

FIG. 2A is a partial cross section showing how the carriers are transported and how they are subjected to bias forces. Specifically, FIG. 2A shows a drive bar 240 mounted on three magnetic wheels 267 mounted on a shaft 268. Shaft 268 extends beyond the chamber wall 269 so that it is rotated from outside the chamber's internal vacuum environment. Further, the shaft 268 is connected to the motor via a flexible belt such as an O-ring so as to adapt to changes in the shaft diameter.

FIG. 2B shows an example of a carrier for processing a silicon wafer, for example, for manufacturing a solar cell. In FIG. 2B, the wafer 220 can be chucked into the susceptor 223 using, for example, a chuck potential. The lifter 215 can be used to raise and lower the wafer for loading and unloading. FIG. 2C shows an embodiment in which the carrier can be used to process a glass substrate such as a touch screen. In this embodiment, the substrate may be secured in place using mechanical spring-loaded clamps or clips 227. The susceptor 224 may be a simple pallet with an instrument for spring-loaded clips.

3A and 3B show embodiments of a substrate load / unload mechanism, along with carrier return. FIG. 3A is a plan view of the load / unload mechanism, and FIG. 3B is a side view. As shown in FIG. 1A, the conveyor returns the carrier after the process is complete. The carrier is then lowered by the elevator 107 and transported horizontally to the load / unload station 105. As shown in FIGS. 3A and 3B, the dual conveyors, ie conveyor 301 and conveyor 303, are used to move the untreated substrate for processing and remove the processed wafer. Which conveyor moves the unprocessed wafers and which conveyor removes the processed wafers is not really important as the system works exactly the same anyway. Further, in the present embodiment, it is shown that the substrate is conveyed in the opposite directions of the conveyor 301 and the conveyor 303, but the same result can be obtained when both conveyors travel in the same direction.

The configurations of FIGS. 3A and 3B support the simultaneous handling of two carriers. Specifically, in the present embodiment, the treated substrate is unloaded from one carrier, and at the same time, the unprocessed substrate is loaded into another carrier. Further, the treated substrate is placed on the conveyor of the treated substrate, and at the same time, the untreated substrate is picked up from the conveyor of the untreated substrate and moved to the carrier of the next round. This operation is performed as follows.

The substrate pickup mechanism is configured to have two motions, namely a rotational motion and a vertical motion. The four rows of chucks 307 are attached to the substrate pickup mechanism 305. The chuck 307 may be, for example, a vacuum chuck, an electrostatic chuck, or the like. In this particular embodiment, four rows of Bernoulli chucks, i.e. chucks capable of holding the substrate utilizing Bernoulli adsorption, are used. The four rows of chucks are arranged in two rows on each side so that when one of the two rows of chucks is aligned with the carrier, the other two rows are aligned with the conveyor. Thus, when the pickup mechanism 305 is in the lowered position, one row of chucks picks up the treated substrate from the carrier and another row installs the untreated substrate on another carrier, while the other row of one row. A chuck installs the processed substrate on a conveyor and another row of chucks picks up the unprocessed substrate from the other conveyor. After that, when the pickup mechanism 305 takes an ascending position and rotates 180 degrees, the carriers move one pitch at the same time, that is, the carrier having the untreated substrate moves one step, and the carrier from which the processed substrate has been removed has not yet been removed. It moves to the loading position of the processed substrate, and another carrier with the processed substrate moves to the unloading position. After that, the pickup mechanism 305 takes a lowering position, and the process is repeated.

To provide a specific embodiment, in the snapshot of FIG. 3A, the carrier 311 has a treated substrate that is picked up by a row of chucks in the pickup mechanism 305. The carrier 313 is loaded with unprocessed substrates from chucks in other rows of the pickup mechanism 305. On the other side of the pickup mechanism 305, one row of chucks places the treated substrate on the conveyor 303, and another row of chucks picks up the untreated substrate from the conveyor 301. When these operations are completed, the pickup mechanism 305 is raised to the ascending position and rotated 180 degrees as indicated by the curved arrow. At the same time, all carriers move one step, i.e. the carrier 316 moves to a position previously occupied by the carrier 317, and the carrier 313 loaded with the currently untreated substrate was previously occupied by the carrier 316. The currently empty carrier 311 moves to a position previously occupied by carrier 313, and the carrier 318 loaded with the processed substrate moves to a position previously occupied by carrier 311. To do. Then, the pickup mechanism is lowered, the unprocessed substrate is loaded on the carrier 311, the processed substrate is removed from the carrier 318, the substrate removed from the carrier 311 is installed on the conveyor 303, and the unprocessed substrate is placed on the conveyor. Taken up from 301. After that, the pickup mechanism 305 is raised and the process is repeated.

Also, in the embodiments of FIGS. 3A and 3B, an optional mask lifter device 321 is used. In this embodiment, the mask is used to generate the desired pattern on the surface of the substrate, i.e., exposing a predetermined area of the substrate for processing, but covering other parts to prevent processing. Used to. The carrier travels through the system with a mask placed on top of the substrate until it reaches the mask lifter 321. When the carrier having the treated substrate arrives at the mask lifter (FIGS. 3A and 3B, carrier 318), the mask lifter 321 takes an ascending position and lifts the mask from the carrier. The carrier can then proceed to the unload station to remove the processed substrate. At the same time, the carrier having the untreated substrate (FIG. 3B, carrier 319) moves into the mask lifter appliance, the mask lifter 321 takes a descending position and places the mask on the untreated substrate for processing.

As will be appreciated, in the embodiments of FIGS. 3A and 3B, the mask lifter removes the mask from one carrier and places the mask on different carriers. That is, the masks are placed on different carriers without being returned to the carrier from which the mask was removed. Depending on the design and number of carriers in the system, the mask may be returned to the same carrier after a few rounds, but only after it has been removed from another carrier. The reverse is also true, i.e., depending on the design and number of carriers and masks in use, each mask may be used for all carriers in the system. That is, each carrier in the system may be used with each of the masks in the system, and at each processing cycle in the system, the carriers may use different masks.

As shown in the balloon, the carrier elevator can be realized by having two vertical conveyor appliances, one on each side of the carrier. Each conveyor appliance comprises one or more conveyor belts 333 operated by rollers 336. The lift pin 331 is attached to the belt 333, and when the belt 333 operates, the pin 331 engages the carrier and moves the carrier vertically (ie, on which side of the system the elevator is located, and the carrier return conveyor Moves up and down depending on whether it is located above or below the processing chamber).

FIG. 3C shows an embodiment of the substrate alignment mechanism. According to this embodiment, the chuck 345 has a spring-loaded alignment pin 329 on one side and a notch 312 on the other side. The rotary pushpin 341 is configured to enter the notch 312, press the substrate 320 against the alignment pin 329, and retract, as indicated by the dotted line and the rotary arrow. The rotary pushpin 341 is not a part of the chuck 345 or the carrier, and is fixed without moving in the system. Also, when using a mask, the spring urging alignment pin is compressed to a lower position. In this way, the first side configured with the alignment pins, the second side configured with the two alignment pins orthogonal to the first side, and the first side facing each other. A substrate alignment mechanism comprising a chuck having a third side configured with a first notch and a fourth side configured with a second notch facing the second side. Is provided. The alignment mechanism consists of a first push pin configured to enter the first notch and press the substrate against the first alignment pin, and two alignment pins that enter the second notch to push the substrate against the first alignment pin. Further includes a second push pin configured to be pressed against.

FIG. 4 shows an embodiment of a vacuum processing chamber 400 that can be used with the systems of the present disclosure. In the example of FIG. 4, the lid of the chamber has been removed to expose the internal structure. The chamber 400 can be mounted horizontally or vertically without changing its configuration or structure. The chamber consists of a simple box frame with an opening 422 for vacuum pumping. The inlet opening 412 is cut into one side wall so that the carrier 424 can enter the chamber, pass through the entire chamber, and exit the chamber from the other, while the exit opening 413 is on the opposite side wall. It has been cut out. For clarity, only the gate valve 414 is shown in the illustration of FIG. 4, but the gate valves are provided at the inlet opening 412 and the outlet opening 413.

Magnetic wheels 402 are provided on the opposing side walls of the chamber to allow the carrier 424 to be transported efficiently and accurately in the horizontal and vertical directions. The carrier has a magnetic bar mounted on the magnetic wheel 402. The shaft to which the wheel 402 is mounted extends out of the chamber into the atmospheric environment and is driven by a motor 401. Specifically, a plurality of motors 401 are provided, and each of them moves a plurality of shafts using a belt such as an O-ring. Further, the idler wheel 404 is provided so as to limit the carrier in the lateral direction.

The feature of the embodiment of FIG. 4 is that the diameter of the magnetic wheel is smaller than the thickness of the side wall of the chamber. This makes it possible to dispose the magnetic wheel inside the inlet opening 412 and the outlet opening 413, as shown by the wheels 406, 407. By arranging the wheels 406, 407 inside the inlet opening 412 and the exit opening 413, the carrier to the chamber minimizes the gap that the carrier must traverse without receiving support from the wheel. Smooth entry and exit is possible.

FIG. 5 shows an embodiment of a mask and carrier assembly. Proceeding from left to right along the curved arrow, the single substrate mask assembly 501 is mounted on the mask carrier 503 supporting multiple mask assemblies, and the mask carrier 503 is mounted on the substrate carrier 505. Will be done. In one embodiment, the spring between the floating mask assemblies 501 has a guide pin 507 provided on the mask assembly 501 and the substrate carrier 505 so that each mask is aligned with its respective substrate. Hold the position for engagement. Each single substrate mask assembly consists of an inner foil mask that is inexpensive and can be used over and over again. The foil mask is made of a flat sheet-like magnetic material with through holes according to the desired design. The outer mask covers the inner mask and protects the inner mask by taking a heat load, so that the foil mask is not distorted. The outer mask aperture exposes the area of the inner mask that has through holes. The frame holds the inner mask and the outer mask on the mask carrier 503. The magnet embedded in the substrate carrier 505 pulls the inner foil mask into contact with the substrate.

Each substrate support, for example a mechanical chuck or an electrostatic chuck 517, supports a single substrate. The individual chucks 517 can be modified to support substrates of different sizes and / or sizes, and the same system can be used to process substrates of different sizes and types. In this embodiment, the chuck 517 has a stretchable substrate alignment pin 519 that provides alignment of the substrate on the chuck. Further, in the present embodiment, the realization of alignment includes a slit 512 that accommodates a stretchable pin that retracts from the slit 512 after pressing the substrate against the alignment pin 519. This allows the substrate and mask to be aligned with the substrate carrier in the same way that the mask is aligned with the substrate.

It should be understood that the systems described so far are inexpensive to manufacture and provide efficient vacuuming of various substrates such as solar cells, touch screens and the like. The system is configured to load and unload the board in double or single, i.e. load and unload the board from one side, or load from one side and unload from the other side. It may be configured to do so. The substrate is not handled in vacuum. The system is modular and the required number of vacuum processing chambers may be provided between the inlet and outlet of the load lock. The vacuum chamber has a simple configuration with few components in the vacuum. The vacuum chamber may also be mounted horizontally or vertically. The system may process the substrate horizontally, for example, in the case of solar cell processing, but may process the substrate vertically in the case of touch screen processing. In any case, loading, unloading, and transporting in the atmospheric environment is done on a horizontal substrate. Processing sources, such as sputtering sources, may be mounted above and / or below the substrate. The system may perform pass processing or static processing, i.e., the substrate can be processed in a stationary or moving state during vacuum processing. The chamber may accommodate sputter sources, heaters, injection beam sources, ion etching sources and the like.

When applied to solar, the vacuum chamber may include a low energy injection device (eg, less than 15 KV). For example, in the design of certain solar cells such as PERC, IBC, or SE, masking equipment may be used to mask the injection. Texture etching may also be performed with or without a mask using an ion etching source or laser assist etching. In point contact batteries, masks with a large number of holes aligned with the contacts may be used. Further, a thick metal layer may be formed by sequentially arranging a plurality of PVD chambers and continuously stacking them to form a layer.

When applied to touch panels, the chamber may be used to deposit cold and / or hot ITO layers using PVD sources. In order to obtain higher throughput with simple handling, the process is such that multiple, eg, three touch panels are placed in each carrier in the width direction, and multiple, for example, two carriers are placed simultaneously in each chamber. It may be done. The same system can handle touch screens used in pad or cell phone sized glass without internal relocation. Simply configure the appropriate carriers and the entire system will remain the same. Similarly, the substrate is not handled in vacuum.

Handling and processing operations may be similar for substrates of all types and sizes. Empty carriers move from the carrier return elevator to load. When using a mask, the mask is removed and stays in the elevator. The substrate is loaded onto the carrier in an atmospheric environment. The carrier returns to the elevator and the mask is placed on top of the substrate. The carrier then moves into the load lock. In vacuum, carrier transfer is carried out by a simple magnetic wheel, which is located on the chamber wall and is driven from outside the chamber in an atmospheric or vacuum environment. The chamber may be provided with a separation valve and may have a source in the drawer for processing above or below the substrate. The board may be removed at the unload end of the system or may return to the load end, i.e. the inlet side of the system, while still mounted on the carrier. Carriers are returned by a simple conveyor belt from the process end of the system to the load end of the system. A simple pin conveyor raises or lowers carriers to the load station or from the unload station.

6A-6C show three embodiments that reveal how the vacuum chamber fits into different processing sources of various sizes and configurations. In the embodiment of FIGS. 6A to 6C, it is assumed that three substrates are arranged in the width direction, but of course, more or less substrates may be arranged in the width direction of the carrier. Also, in FIGS. 6A-6C, it is envisioned that the processing chamber can accommodate a plurality of carriers, such as two or three carriers, for simultaneous processing. The source shown in FIGS. 6A-6C may be any processing source such as PVD, etching, implant.

FIG. 6A shows an embodiment in which a single source 601 is provided in chamber 600. This single source is used to process all substrates located within chamber 600. Source 601 may have a length and / or width that covers all substrates at the same time. For some sources, configuring a single source with such a large size can be very complex or expensive. For example, if the source 601 is a sputtering source, the target needs to be very large, which is expensive, complex and underutilized. Therefore, in the embodiments of FIGS. 6B and 6C, a plurality of smaller sources are used. In the embodiment of FIG. 6B, each of the sources 603A-603C has a width sufficient to cover only a single substrate, but covers one or more substrates in the longitudinal direction, i.e. in the traveling direction of the substrate. be able to. All substrates can be processed by shifting each source so that each source covers only one of the substrates in each carrier. Such source placement is particularly suitable for transit processing. On the contrary, in the embodiment of FIG. 6C, each of the sources 606A-606C has a width sufficient to cover all the substrates in one carrier, that is, all the substrates in the direction orthogonal to the traveling direction of the substrates. , Not enough to cover all the substrates located in the chamber. In fact, in some embodiments, each of the sources 606A-606C is even thinner than a single substrate. Such source placement is similarly suitable for transit or static processing.

In the above embodiments, a vacuum processing chamber is provided that includes a vacuum housing sized to simultaneously accommodate and process a plurality of substrate carriers. The housing is also configured to support multiple processing sources at the same time. The processing source is, for example, a sputtering source, which is a thin source having a length sufficient to traverse all the substrates held by the substrate carrier, but can be narrower than the width of the substrate located on the carrier. There may be. A plurality of such sources may be placed facing each other over the entire length or portion of the chamber in the direction of carrier travel. The chamber has a plurality of shafts located on two opposite sides so as to carry the carrier into the chamber. Each shaft is rotated by a flexible belt driven by a motor. Further, each shaft includes a plurality of magnetic wheels arranged on the shaft in an order of alternating polarities, that is, an outer peripheral portion in which one wheel is magnetized to the S pole and an inner diameter portion magnetized to the N pole. On the other hand, the adjacent wheel includes a plurality of magnetic wheels having an outer peripheral portion magnetized to the north pole and an inner diameter portion magnetized to the south pole. Further, the chamber includes an inlet side wall having an inlet opening and an outlet side wall having an outlet opening facing the inlet side wall. In that chamber, a magnetic wheel fixture located in the inlet side wall and protruding into the inlet side wall to drive a substrate carrier passing through the inlet and outlet openings and an exit opening placed in the outlet side wall. It has a magnetic wheel fixture that protrudes into the part.

The system of the present disclosure is a linear system, in which the chambers are all arranged linearly with one chamber connected to the next and the substrate carrier entering the system from one side. Cross the chamber in a straight line and leave the system on the other side. The carrier moves directly from one chamber to the next chamber via a gate valve that separates the chambers. Upon exiting the system's vacuum environment, the carrier enters the elevator and travels vertically to the return conveyor. The return conveyor horizontally transports the carrier back to the inlet side of the system. The carrier then enters another elevator, moves vertically, loads the raw substrate, and reenters the system's vacuum environment. The carrier is held horizontally when transported in an atmospheric environment. However, in one embodiment, when the carrier enters the vacuum environment, it is rotated vertically to process while holding the substrate vertically.

The system may have a load / unload station located on the entrance side of the system. The load / unload system has a rotary structure in which four rows of chucks are arranged and two rows are arranged on each side of the rotary shaft. On each side of the rotating shaft, a row of chucks is configured to remove the treated substrate and a row of chucks is configured to load the untreated substrate. The rotating structure is configured to operate vertically, the structure picks up the substrate when in the descending position and the structure rotates 180 degrees when in the ascending position. Also, when the structure is in the descending position, on each side of the axis of rotation, one row of chucks picks up the substrate and the other row of chucks installs, or releases, the substrate. In one embodiment, two conveyors are provided over the inlet to the system, one of which transfers the untreated substrate and the other of which removes the treated substrate. The rotating structure is configured such that in the descending position one row of chucks is aligned with the conveyor that transfers the untreated substrate and the other row of chucks is aligned with the conveyor that removes the treated substrate. At the same time, on the other side of the axis of rotation, the chucks in one row are aligned with the empty carriers and the chucks in the other row are aligned with the carriers holding the treated substrate.

In some embodiments, it is provided to apply an electric potential to the substrate. Specifically, each carrier includes a conductive strip. As the carrier enters the processing chamber, the conductive strip is inserted into a slide contact that includes an elongated contact brush and a conformal insulating spring that is configured to press the conductive strip against the elongated contact brush. Insulating springs, such as Kapton strips, may be used to attach the conductive strips to the carrier.

When the use of masks is required to process the substrates, the masks may be placed individually on each substrate, or one mask may be formed to cover all the substrates of one carrier at the same time. Good. The mask may be held in place by, for example, a magnet. However, since the mask needs to be formed very thin for accurate processing, it may be deformed by thermal stress during processing. In addition, thin masks can quickly take up deposits, which can interfere with the exact location of the mask and masking. Therefore, it is advantageous to use the dual mask device according to the embodiment disclosed below.

7A-7E show diagrams of multi-wafer carriers with dual masking appliances according to various embodiments. FIG. 7A shows a multi-wafer carrier with dual masking instruments, in which the masking instrument is placed in a lowered position so that the inner mask is in close contact with the wafer for physical contact. FIG. 7B shows a multi-wafer carrier with dual masking appliances, in which the masking appliance is placed in an elevated position to allow wafer replacement. FIG. 7C shows a multi-wafer carrier with dual masking equipment, in which a wafer lifter is included to load / unload wafers. FIG. 7D shows a partial cross section of a multi-wafer carrier with dual masking instruments, in which the masking instrument and wafer lifter are in elevated positions. Further, FIG. 7E shows a partial cross section of a multi-wafer carrier equipped with a dual mask instrument, in which the mask instrument and the wafer lifter are in the lowered position.

Referring to FIG. 7A, the multi-wafer carrier 700 (also referred to as carrier support) has three separate single wafer carriers or susceptors 705 supported by a susceptor frame or bar 710, such as made of ceramic. Each single wafer carrier 705 is configured to hold a single wafer with a dual masking instrument. In FIG. 7A, the dual mask device is in the lowered position, but all carriers are not provided with wafers to show the carrier configuration. In FIG. 7B, the dual mask appliance is shown in the raised position, as well as no wafers on all carriers. In the embodiments of FIGS. 7A-7E, the lifter 715 is used to raise and lower the dual mask device, but for low cost and simplification, the lifter 715 may be omitted and the dual mask device is manual. You may raise it with. Conveyance rails 725 are provided on each side of the frame 710 to allow the carrier 700 to be transported throughout the system.

Each single wafer carrier 705 comprises a base 730 (shown in FIG. 7B), which base has a raised frame 732 with recesses 735 for suspending and supporting the wafer by its periphery. The base 730 with the frame 732 forms a pocket 740 under the suspended wafer, which is useful for catching broken wafer debris. In some embodiments, the frame 732 is separable from the base 730. The outer mask 745 covers the frame 732 and the peripheral edge of the inner mask, but is mounted on the frame 732 so as to expose the central portion of the inner mask corresponding to the wafer. This is illustrated by the cross-sectional view of the embodiment of FIG.

In FIG. 8, the base or susceptor 805 has a raised frame 830 with a recess 832, the recess 835 supporting the wafer 820 at its periphery. The base 805 with the frame 830 forms a pocket 840, and the wafer is suspended above the pocket. A series of magnets 834 are arranged within the raised frame 830 so as to surround the peripheral edge of the wafer 820. In some embodiments, especially in high temperature operations, the magnet 834 may be composed of samarium cobalt (SmCo). The inner mask 850 is placed on the raised frame 830 and the wafer 820 and is held in place by the magnet 834 so as to make physical contact with the wafer. The outer mask 845 is placed on top of the inner mask 850 so as to physically contact the inner mask 850 and cover the periphery of the inner mask 850 except for the area of the inner mask configured to process the wafer. To do. FIG. 9 shows an example of an outer mask 945 made of a folded aluminum sheet. Since this embodiment is for edge shunt isolation processing, in this embodiment the inner mask is covered by the outer mask except for the small peripheral edge 952. FIG. 10 shows an example of an inner mask 750 for edge shunt separation. The inner mask 750 is a metal flat sheet having an aperture that is basically the same size and shape as the wafer, except that it is slightly smaller than the size of the wafer, for example, 1 to 2 mm. In the embodiment of FIG. 8, the mask frame 836 is provided so as to support and raise and lower the inner and outer masks of the carrier. In such a configuration, the outer mask is sandwiched between the mask frame 836 and the inner mask 850.

FIG. 8A shows another embodiment that can be used, for example, to form a contact pattern on the back of a wafer. In this embodiment, the susceptor is formed with an upper platform to support the wafer over its entire surface. The magnet 834 is embedded over the entire area under the top surface of the susceptor. The inner mask 850 covers the entire surface of the wafer 820 and has a plurality of holes corresponding to the contact design.

Returning to FIGS. 7A-7E, the lifter 715 may be used to raise the outer mask along with the inner mask. The wafer lifter 752 may also be used to lift and remove the wafer from the frame 730, which may be replaced with an untreated substrate wafer using a robotic arm for processing. However, the lifters 715 and 752 may be omitted and the mask lifting operation and wafer replacement may be performed manually instead.

In the embodiment described above with reference to FIG. 8, the carrier supports the wafer at its peripheral edge so that the wafer is suspended. Pockets formed under the wafer trap broken wafer debris and prevent sedimentary material from wrapping around. On the other hand, in the embodiment of FIG. 8A, the wafer is supported over its entire surface. The mask assembly descends to a predetermined position for sputtering or other forms of processing and ascends manually or mechanically for wafer loading and unloading. A series of magnets in the carrier are utilized to ensure the position of the inner mask and the close contact between the inner mask and the wafer. After repeated use, the outer and inner masks may be replaced, but the rest of the carrier assembly can be reused. The frame 810 (also referred to as the mask assembly sidebar) may be constructed of a low thermal expansion material such as alumina or titanium.

According to the above-described embodiment, the inner mask is in close contact with the substrate without any gap. The outer mask protects the inner mask, carrier and frame from the deposited material. In the embodiments described, the openings of the outer and inner masks are substantially square, making them suitable for application to single crystal solar cells in edge shunt separation processes. In other processes, the inner mask has a predetermined aperture and the outer mask has a substantially square aperture. A substantially square is a square with corners cut out corresponding to a circular ingot from which the wafer is cut. Of course, when a square polycrystalline wafer is used, the openings between the outer mask and the inner mask are also square.

FIG. 11 shows an embodiment of a single wafer carrier 1105. The wafer is placed in the recess 1132 on its peripheral edge. The magnet 1134 shown by the broken line is provided in the carrier on the entire circumference of the wafer. The alignment pin 1160 is used to align the outer mask to the carrier 1105. An embodiment of the outer mask is shown in FIG. 12 from a lower perspective. The outer mask 1245 has an alignment hole or recess 1262 corresponding to the alignment pin 1260 of the carrier 1205.

FIG. 13 shows an embodiment of a top frame 1336 used to hold the outer and inner masks and secure the masks to the susceptor. The top frame 1336 may consist of, for example, two vertical bars 1362 held together by two horizontal bars 1364. The outer mask is held in pocket 1366. Alignment holes 1368 are provided to align the top frame with the susceptor.

FIG. 14 shows an example of an inner mask with a hole pattern designed to produce a plurality of contacts on a wafer, for example. Such an inner mask may be used with the susceptor shown in FIG. 15, where magnets 1534 are distributed over the entire area beneath the surface of the wafer. The magnets are oriented with alternating polarities.

The top mask or outer mask may be made of, for example, about 0.03 inch thin aluminum, steel or other similar material and is configured to connect with the substrate carrier. The inner mask is made of, for example, a very thin steel flat sheet of about 0.001 inch to 0.003 inch, or other magnetic material and is configured to fit inside the outer mask.

According to a further embodiment, an arrangement for supporting the wafer during processing is provided, the arrangement with a wafer carrier or susceptor having a raised frame and an inner mask configured to be located on the raised frame. Includes an outer mask configured to be placed on a raised frame over the inner mask. The raised frame has recesses that surround the periphery of the wafer to support the wafer and confine the wafer in place. The inner mask has an aperture configured to mask a portion of the wafer to expose the rest of the wafer. The outer mask has a single opening configured to partially cover the inner mask. The top frame carrier may be used to hold the inner and outer masks and secure the inner and outer masks to the wafer susceptor.

The magnets are arranged on the susceptor, alternating with N-SN-SN, surrounding the entire perimeter of the frame, or completely below the entire surface of the susceptor and directly below the wafer. The outer and inner masks are designed to be held in the frame solely by magnetic force to allow for convenient and quick loading and unloading of the substrate.

The mask assembly is removable from the wafer carrier and the support frame for loading the substrate into the carrier. Both the outer and inner masks are lifted as part of the mask assembly. When the wafer is placed in the wafer pocket on the carrier, the mask assembly is lowered back into the carrier. The inner mask overlaps the upper surface of the wafer. The magnet of the carrier frame pulls down the inner mask so that it is in close contact with the substrate. This forms a tight compliant seal on the edge of the wafer. The outer mask is designed to prevent deposition on the thin compliant inner mask. As described above, the deposition process generates heat in the inner mask, causing the mask to warp and poor contact between the mask and the wafer. When poor contact between the mask and the wafer occurs, the metal film is deposited in the exclusion area on the surface of the substrate wafer. The frictional force of the pockets and magnets prevents the substrate and mask from moving relative to each other during transport and deposition, and the outer mask prevents film deposition on the inner mask and prevents warping of the inner mask.

The mask assembly may be periodically removed from the system along with the carriers by using a vacuum carrier exchanger. A carrier switch is a portable vacuum enclosure with a carrier carrier. This allows carrier replacement "on the fly" without interrupting continuous operation of the system.

16A-16D show embodiments that can be implemented within a load station, such as the load station 105. In this embodiment, a wafer plate is used to support the wafer, the wafer plate is detachably attached to the carrier from below, while the dual mask is attached from above. For brevity, FIGS. 16A-16D show only relevant parts of the system. Also, some elements have been removed to show the characteristics of this embodiment.

In FIGS. 16A-16D, the carrier 1600 is in the shape of a substrate to be processed, eg, a semiconductor wafer, but is a simple frame with a plurality of openings 1602 that can be slightly larger to allow passage of the substrate. 1605 is provided. A plurality of wafer plates 1610 are attached to the bottom of each carrier 1600. The wafer plate 1610 is typically a simple form of aluminum plate and may include mounting fixtures for mounting the wafer plate under the carrier 1600. When the wafer plate 1610 is attached to the carrier 1600, the substrate 1620 arranged in front of the wafer plate 1610 is aligned with the opening 1602 and exposed through the opening. Mounting fixtures may include mechanical clips, springs, magnets and the like. In the illustrated embodiment, a plurality of magnets 1612 (FIG. 16C) are used as attachments.

The mask appliance 1649 is placed above each carrier 1600 such that each mask appliance 1649 covers one substrate exposed through the opening 1602. The masking instrument 1645 may be a double masking instrument similar to that shown in FIGS. 9 and 10, but other instruments may be used in response to the processing performed. As an example, FIG. 16E shows a double masking instrument in which the inner mask 1650 is, in this example, a simple stamped metal flat sheet made of paramagnetic material. The outer mask 1645 is a simple aluminum plate that is similar in shape to the openings in the inner mask but has a slightly larger opening. It is mentioned that in this dual mask instrument, only the inner dimensions of the inner mask opening are important, and all other dimensions do not require high manufacturing tolerances, thus reducing the complexity and cost of manufacturing the mask. Will be done. Further, in this instrument, the mask is attached in a direction fixed to the carrier so that the opening of the inner mask 1650 is aligned with the opening 1602 of the carrier 1600.

For clarity, the carrier 1600 is shown to be suspended in some figures, but is of course supported and carried by a carrier such as that shown in FIG. 1A. On the other hand, the wafer plate moves independently on the dedicated conveyor belt 1632 until it is transferred to stage 1664 and attached to the carrier 1600. The operation of this mechanism is as follows. A lift mechanism 1662 is provided to load the wafer plate 1610 onto a wafer plate linear conveyor 1663, such as a conveyor belt. Wafers placed on each wafer plate 1610 are aligned to the opening of the inner mask 1650 (using the camera 1670) and then each wafer plate 1610 is aligned so that the wafer plates are lifted and attached to the carrier 1600. A stage mechanism 1664 is provided for this purpose. In this embodiment, when the wafer plate is placed on the stage 1662, a vacuum is applied through the holes 1614 of the wafer plate 1610 to hold the wafer and not move the wafer during the alignment operation. When the wafer plate is attached to the carrier 1600, the vacuum can be stopped because the clamp of the wafer plate to the carrier hinders the movement of the wafer.

Further, a loading mechanism 1605 (FIG. 16D) can be used to load the substrate onto the wafer plate 1610. In particular, the substrate can be loaded onto the wafer plate 1610 before the carriers are loaded onto the wafer plate 1610. As an example, in the case shown in FIG. 16A, the two wafer plates (identified as A and B) do not have a wafer and one wafer plate (identified as C) is placed on it. It has wafers that are but not attached to the carrier 1600, and one wafer plate (identified as D) has wafers that are placed on it and lifted and attached to the carrier 1600. The sequence is shown.

The embodiments shown in FIGS. 16A to 16D are advantageous in that the transfer of the wafer plate for loading and unloading the wafer is performed separately from the transfer of the carrier and the mask. In this way, the wafer plate can be removed from the system for cleaning. Also, since the wafer plate is made from relatively inexpensive aluminum ingots, it can be easily replaced with a new one without affecting the operation of the system.

As clearly shown in FIGS. 16B and 16D, the empty carrier 1600 is transferred by elevator 1635 to the work station and placed on a conveyor, eg, conveyor belt 1633. In this embodiment, each carrier is configured to accommodate two wafer plates for processing two wafers simultaneously, but can also be configured to accommodate a number of other wafer plates. Another conveyor, for example the conveyor belt 1632, transfers the wafer plate 1610 under the conveyor 1633. For example, a wafer loading mechanism, which is a robot 1605, arranges wafers on a wafer plate 1610. When the wafer is placed on the wafer plate 1610, the conveyor 1632 moves the wafer plate 1610 to an alignment station above the alignment stage 1664. A vacuum pump 1647 is then used to supply the suction force to the wafer plate, holding the wafer on the wafer plate and holding the wafer plate on the alignment stage. Specifically, the wafer plate has a vacuum hole 1614 under the wafer. When sucked through these holes 1614, the wafer is held on the wafer plate to seal these holes. As a result, the wafer plate is held in the alignment stage by vacuum by the same suction blocked by the wafer. On the other hand, the conveyor 1633 transfers the empty carrier 1600 to the alignment station directly above the stage 1664. The carrier of the alignment station has a mask device 1649 mounted over the opening 1602. To align, the actuator 1667 lifts the carrier 1600 from the conveyor so that the carrier is mechanically held in a stationary position. The stage 1664 then lifts the wafer plate and rotates or moves it as needed to align the wafer with the opening of the mask 1645 as determined by the controller 1671 using the image acquired by the camera 1670. I do. Once properly aligned, the stage further raises the wafer plate until it contacts the underside of the carrier. At this point the vacuum is stopped so that the wafer plate can be attached to the carrier by mechanical or magnetic means. Stage 1664 then descends to receive another wafer plate, while conveyor 1633 moves the loaded carriers from the alignment station, transfers the unload carriers and repeats the process.

In one embodiment, the method of loading and processing the substrate proceeds as follows. Carriers without wafers return from the unload station. In the embodiment in which the wafer plate is transferred by being attached to a carrier, the wafer plate is removed from the carrier and lowered onto a conveyor by, for example, a lift mechanism 1662. Alternatively, the wafer plate 1610 may be transferred separately from the carrier. The loading mechanism is one wafer for each wafer plate, and a plurality of wafers are arranged on the corresponding wafer plates. The wafer plate and carrier are then moved separately to an alignment station where the camera 1670 images the wafer and mask. The image is provided to controller 1671, which checks the alignment of the mask opening with respect to the wafer. That is, in this particular embodiment, the mask 1645 is attached to the carrier in a fixed orientation. The wafer carrier is placed on the xyz-θ stage 1664 placed below the camera. The controller 1671 uses the image provided by the camera 1670 to calculate the position / orientation of the wafer with respect to the mask opening and signals the stage 1664 to move or rotate the xyz-θ stage 1664. Correct the direction as needed by letting it. The wafer plate is then lifted by the stage and attached to the carrier, and the wafer is placed in contact with the inner mask. At this position, the wafer plate is magnetically held in the carrier to prevent the wafer from moving and the vacuum can be released. Also, the same magnetic force holds the dual masking device pressed against the wafer. As a result, the wafer cannot move from its aligned position. That is, in one embodiment, when the wafer plate is located at the alignment station and the wafer is placed at the aligned position, a vacuum is applied to the wafer via the wafer plate so that the wafer does not move. However, when the wafer plate is attached to the carrier and the mask comes into contact with the wafer, vacuum pumping can be stopped. The carrier is then moved across the system for processing and the sequence is repeated when processing is complete.

In one embodiment, after processing is complete, the wafer is removed from the wafer plate at the unload station and the wafer plate is tilted vertically. Therefore, even if the wafer is damaged during processing, it is realized that the debris is removed before returning the wafer plate for further processing.

FIG. 16F is a cross section of a portion of the system, the enlarged portion of which is shown in the balloon. It can be seen that in this embodiment a dual mask device is used in which the inner mask 1650 is covered by the outer mask 1645. A magnet 1612 is provided around the wafer plate 1610 to hold the wafer plate 1610 under the carrier 1605.

In certain embodiments, the following sequence is performed, in which each carrier can support 5 wafer plates. Five wafers are loaded onto five individual wafer plates. The five loaded wafer plates are then moved to the alignment station. In this particular embodiment, each wafer plate has a gasket with magnets around the edges. Gaskets may be made of fluoroelastomers classified by the FKM label of ASTMD1418 and ISO1629. At the alignment station, five wafer plates are lifted from the conveyor by the alignment stage (here, five separate alignment stages are provided to align the five wafer plates at the same time). When the wafer plate is lifted from the conveyor, the vacuum ensures that the wafer plate is held on the lift and that the wafer is held on the wafer plate. At this point, the five wafers are individually imaged by the five cameras. The conveyor then moves the carriers to an alignment station directly above the wafer plate so that each opening of the carrier is above one of the wafer plates. The carrier is then lifted from the conveyor belt to place the carrier in a mechanically fixed stationary position. The camera is then activated to image the five openings on the carrier. The system then calculates the x-axis and y-axis of each mask opening, as well as the x-axis and y-axis of each of the five wafers. The five X / Y / θ stages then move each wafer to align the x-axis and y-axis of each wafer with the x-axis and y-axis of the corresponding mask. The five wafer plates are then lifted until the wafer plates are in contact with the carriers and attached so that the wafers on each wafer plate are placed in the corresponding openings of the carriers and in contact with the corresponding inner masks. The vacuum is then released and the wafer plate is mechanically or magnetically attached to the carrier at this point. The carrier and stage are then lowered and the sequence is repeated for the second row.

FIG. 16G shows another embodiment of the wafer plate 1610. In this embodiment, the wafer plate 1610 is again made of ingot aluminum. Three vacuum mesas 1613 are provided on the front surface of the wafer plate 1610, and each mesa has a vacuum hole 1614. In one embodiment, the mesas are made of a soft material and each mesa includes a seal portion 1611 around each hole 1614. Therefore, when the wafer is placed on the wafer plate 1610 and a vacuum is applied to the mesas, the wafer is held by the vacuum on the three mesas so as not to contact the surface of the wafer plate 1610. Since only three mesas are provided, no force is applied to the wafer and the wafer does not bend or break. In addition, a buffer ring 1618 is provided on the periphery of the wafer plate 1610. A magnet 1612 is embedded in the buffer ring 1618. In this embodiment, the buffer ring does not provide an airtight seal on the wafer to avoid pulling the wafer into the surface side of the wafer plate 1610. This is done, for example, by making the buffer ring 1618 made of a porous material or by providing an air channel 1619 that communicates from the ambient environment to the space between the wafer and the top surface of the wafer plate 1610.

FIG. 16H shows the top surface of a seat plate 1672 that can be adapted to either the load stage 1669 and / or the alignment stage 1664 according to one embodiment. The seat plate 1672 is mounted on the load stage 1669 and the alignment stage 1664, and the wafer plate 1610 is placed on the seat plate 1672. As shown in FIG. 16H, two sets of vacuum holes are formed through the top surface of the sheet plate 1672. The first set of holes 1668 is aligned with the corresponding vacuum holes 1614 of the wafer plate 1610 to provide a vacuum passage for attracting the wafer to hold the wafer in the wafer plate 1610. The second set of holes 1667 provides a suction force that holds the wafer plate 1610 on the sheet of the alignment stage 1664. Thus, in one embodiment, when the carrier is transferred to the load station, the load stage rises, suction is performed in at least the second set of holes 1667, and vacuum forces attach the corresponding wafer plates to each load stage. To do so. When the load stage is lowered, the wafer plate 1610 is separated from the carrier by the vacuum force holding the wafer plate on the sheet plate 1672. In one embodiment, there is no need to apply vacuum to the holes 1668 (wafers are unloaded at the unload station during this process) as the carriers return without the wafer. In practice, these holes may be closed, or the load stage may be provided with a sheet plate 1672 having only vacuum holes 1667.

FIG. 16I shows the top surface of the seat plate 1674 that can be adapted to the unload stage, for example in the carrier return chamber 135 shown in FIGS. 1, 1A and 1B. The seat plate 1674 is mounted on the unload stage and the wafer plate 1610 is placed on the seat plate 1674. As shown in FIG. 16I, the first set of holes 1668 is blocked or not provided so that there is no vacuum passage to the corresponding vacuum holes 1614 on the wafer plate 1610. That is, in the unload stage, the wafer is not sucked so as to hold the wafer on the wafer plate 1610. The second set of holes 1667 provides a suction force that holds the wafer plate 1610 on the sheet of the alignment stage 1664. Thus, in one embodiment, when the carrier is transferred to the unload station, suction is performed on the holes 1667 to hold the corresponding wafer plate by vacuum force. Next, the unload stage tilts the sheet plate 1674 as shown by the curved arrow, and if there is a broken wafer fragment on the wafer stage 1610, the fragment slides off the wafer plate 1610 and becomes a recovery trough 1682. Try to enter.

As understood from the above disclosure, a system for processing wafers is provided, the system having a load sheet plate with a first set of suction holes and a load stage that is vertically movable. And a fourth set of alignment stations, including an alignment sheet plate with a second set of suction holes and a third set of suction holes, as well as an alignment stage that is movable in the xyz and rotational directions. An unload seat plate with a set of suction holes and an unload stage that is movable in the vertical and tilt directions so that the unload seat plate is vertical when the unload stage moves in the tilt direction. A load station, at least one vacuum processing chamber located between the alignment station and the unload station, and a wafer plate each configured to support one wafer and placed on the wafer plate. A plurality of wafer plates having a fifth set of suction holes configured to add vacuum to the formed wafer and a plurality of wafer plates are continuously mounted from a load station, an alignment station, a vacuum processing chamber, and the like. The first set of suction holes, the second set of suction holes, and the fourth set of suction holes include a transfer device configured to carry to the unload station and back to the load station. , The wafer plate is configured to add vacuum, and the third set of vacuum holes is aligned with and communicated with the fifth set of suction holes. The system further comprises a plurality of carriers and a plurality of masks, each carrier being configured to support a plurality of wafer plates from below the carriers, and each mask can be mounted on one top surface of the carrier. ..

Each wafer plate contains three mesas, and each mesa can contain one of the suction holes. Each mesa may further include a seal around the suction hole. Each wafer plate can further include a buffer ring and a plurality of magnets attached to the buffer ring. The system can include a container configured to receive wafer fragments from the wafer plate as the unload station moves in the tilt direction. The alignment station may further include a camera aligned to image a wafer placed on a wafer plate mounted on the alignment stage and image a mask attached to a carrier. The controller also receives an image from the camera and sends an alignment signal to the alignment stage to align the wafer with the mask. The conveyor belt can include a first conveyor belt configured to convey the carrier and a second conveyor belt configured to convey the wafer plate.

Although the present invention describes specific members and exemplary embodiments of specific stages, modifications of these particular embodiments can be made and / or used, and such structures and methods are described. , And can arise from the understanding gained by the description and illustrated examples, and by the study of operations that allow modifications that can be made without departing from the scope of the invention as defined in the appended claims. Needs to be understood by those skilled in the art.

Claims (28)

A system for processing wafers in a vacuum processing chamber.
A plurality of carriers, each of which comprises a frame having a plurality of openings, each of which is configured to accommodate a wafer.
A transport device configured to transport the plurality of carriers in the system, and
In a mounting device for mounting a plurality of wafer plates and a plurality of wafer plates to each of the carriers, each of the wafer plates is configured to support one wafer, and each of the wafer plates is the wafer plate. A mounting fixture, which is mounted at a corresponding position below the corresponding carrier so that each of the wafers placed in one of the carriers is placed in one of the plurality of openings of the carrier.
A plurality of masks, each of which is attached to the front side of one of the plurality of openings of the carrier.
An alignment stage configured to support one of the wafer plates below one of the plurality of openings in the carrier and configured for moving, rotating, and ascending operations.
A camera arranged to take an image of one of the plurality of masks and to take an image of a wafer arranged on one of the wafer plates when the wafer plate is arranged on the alignment stage.
A system including a controller that receives an image from the camera and transmits a correction signal to the alignment stage. The plurality of masks include a plurality of inner masks and a plurality of outer masks.
Each of the plurality of inner masks is configured to be placed on one of the plurality of openings in the carrier and is open to mask a portion of the wafer and expose the rest of the wafer. Has a pattern and
The system of claim 1, wherein each of the plurality of outer masks is configured to be placed on top of a corresponding inner mask and has an opening configured to partially cover the inner mask. The system according to claim 1, wherein each of the wafer plates is a flat plate made of aluminum. The system according to claim 3, wherein the attachment includes a plurality of magnets attached to each of the plurality of wafer plates. The system according to claim 4, wherein each of the plurality of wafer plates further includes a vacuum hole. The system of claim 1, further comprising a conveyor belt configured to transport the wafer plate to a position within the field of view of the camera. The transport device includes a first linear conveyor configured to transport the carrier when the wafer plate is removed from the carrier, and a second linear conveyor configured to transport the wafer plate. , The system according to claim 1. The alignment stage includes a sheet plate, which performs suction to hold a first set of vacuum holes aligned with the vacuum holes in the wafer plate and the wafer plate in the sheet plate. The system according to claim 5, further comprising a second set of vacuum holes configured as described above. Further including an unload stage including an unload sheet plate, the unload sheet plate blocks the vacuum holes of the wafer plate to prevent communication with the vacuum holes, and makes the wafer plate the unload sheet. The system of claim 5, comprising a set of vacuum holes configured to perform suction for holding on a plate. The system of claim 1, further comprising a substrate unload station having a mechanism for vertically tilting the wafer plate onto a collection container to recover arbitrary substrate debris from the wafer plate. A system for processing wafers
A load station with a load sheet plate with a first set of suction holes and a load stage that is vertically movable.
An alignment station comprising an alignment sheet plate having a second set of suction holes and a third set of suction holes and an alignment stage that is movable in the xyz and rotational directions.
It has an unload seat plate with a fourth set of suction holes and an unload stage that is movable in the vertical and tilt directions, and when the unload stage moves in the tilt direction, the unload seat plate is in the vertical direction. Become an unload station and
With at least one vacuum processing chamber located between the alignment station and the unload station,
A plurality of wafer plates each having a fifth set of suction holes configured to support one wafer and to apply a vacuum to the wafers arranged on the wafer plate. When,
The plurality of wafer plates are continuously transported from the load station to the alignment station, the vacuum processing chamber, and the unload station, and are transported so as to return to the load station. Including instruments and
The first set of suction holes, the second set of suction holes, and the fourth set of suction holes are configured to apply a vacuum to the wafer plate, and the third set of suction holes is the first set. A system that is aligned and communicated with 5 sets of suction holes. 11. The system of claim 11, further comprising a plurality of carriers, each of which is configured to support a plurality of wafer plates from underneath the carriers. 12. The system of claim 12, further comprising a plurality of masks, each of which is mounted on one top surface of the carrier. 11. The system of claim 11, wherein each of the wafer plates comprises three mesas, and each of the mesas comprises one of the suction holes. 14. The system of claim 14, wherein each of the mesas further comprises a seal around the suction hole. 14. The system of claim 14, wherein each of the wafer plates further comprises a buffer ring and a plurality of magnets attached to the buffer ring. 11. The system of claim 11, further comprising a container configured to receive wafer fragments from the wafer plate as the unload station moves in an inclined direction. 13. The alignment station further comprises a camera aligned to image a wafer placed on a wafer plate mounted on the alignment stage and to image a mask attached to a carrier. The system described in. 18. The system of claim 18, further comprising a controller that receives an image from the camera and transmits an alignment signal to the alignment stage to align the wafer to the mask. The system according to claim 12, wherein the transfer device includes a first conveyor belt configured to convey the carrier and a second conveyor belt configured to convey the wafer plate. A method for processing wafers in a vacuum processing chamber.
A step of attaching a mask that overlaps the opening of the carrier on the upper surface of the carrier,
The step of loading the wafer on the top surface of the wafer plate,
A step of transporting the wafer plate provided with the wafer to the alignment station and arranging the wafer plate on the alignment stage.
The step of operating the camera to image the wafer on the alignment stage,
A step of transporting the carrier with the mask to the alignment station,
The step of operating the camera to image the mask,
A step of calculating the misalignment using the image of the wafer and the mask and operating the alignment stage to align the wafer with the mask.
When the wafer is aligned with the mask, the alignment stage is raised and the wafer plate is attached to the underside of the carrier so that the wafer is placed in the opening of the carrier.
The step of lowering the alignment stage and
A method comprising the steps of transporting the carrier to the vacuum processing chamber and processing the wafer. 21. The method of claim 21, further comprising sucking the wafer when the wafer plate is placed on the alignment stage. 21. The method of claim 21, wherein attaching the mask comprises attaching an inner mask to the carrier and attaching an outer mask on the inner mask. 21. The method of claim 21, wherein attaching the wafer plate to the underside of the carrier comprises applying a magnetic force between the wafer plate and the carrier. 24. The method of claim 24, further comprising applying the magnetic force to the mask. A method for processing wafers in a vacuum processing chamber.
The step of transporting the wafer plate to the loading position and loading the wafer onto the wafer plate,
A step of moving the wafer plate to the alignment station and arranging the wafer plate on the alignment stage.
A step of sucking the wafer to hold it on the wafer plate, a step of imaging the wafer using a camera, and a step of calculating the x-axis and y-axis of the wafer from the image.
The carrier is conveyed to the alignment station, the carrier is arranged above the wafer plate so that the opening of the carrier is arranged above the wafer plate, and a mask having a mask opening is the carrier. With the steps placed on
A step of lifting the carrier and placing the carrier in a mechanically fixed stationary position.
The camera is operated to image the mask opening on the carrier, and the step of calculating the x-axis and y-axis of the mask opening and the positioning stage are operated to operate the x-axis and y of the wafer. A step of moving the wafer plate so that the axis coincides with the x-axis and the y-axis of the mask opening.
A step of lifting the wafer plate until the wafer plate is contacted and attached to the carrier so that the wafer is placed in the opening of the carrier.
A method comprising a step of releasing a vacuum and a step of transporting the carrier provided with the wafer plate to the vacuum processing chamber. 26. The method of claim 26, wherein the suction is performed to hold the wafer on the wafer plate and to hold the wafer plate on the stage. Arbitrarily located on the wafer plate by transporting the carrier from the vacuum processing chamber, loading the wafer plate onto the unload stage, and activating the unload stage to tilt the wafer plate. 26. The method of claim 26, further comprising removing a wafer fragment of.