JP4589357B2 - Polishing equipment - Google Patents

Description

  The present invention relates to a polishing apparatus, and more particularly to a polishing apparatus that polishes a polishing object such as a semiconductor wafer into a flat and mirror-like shape.

In recent years, as semiconductor devices are highly integrated, circuit wiring is becoming finer and the distance between wirings is becoming narrower. In particular, in the case of optical lithography of 0.5 μm or less, since the depth of focus becomes shallow, the flatness of the image plane of the stepper is required.
Therefore, it is necessary to flatten the surface of the semiconductor wafer, but polishing is performed by a polishing apparatus as one means of this flattening method.

  Conventionally, this type of polishing apparatus can be broadly divided into a load / unload function for transferring a cassette containing wafers, a transfer function for moving wafers, a polishing function for polishing wafers, and recently cleaning a polished wafer. In order to perform these functions, the apparatus is configured by individually assembling a large number of devices and members for attaching them. Further, as a system for operating and controlling these devices, the power source and the signal are individually connected to the power source and the control device in the control panel of the apparatus.

Conventional polishing apparatuses have the following problems.
(1) Since there are many types of semiconductor wafers that are objects and polishing process conditions differ depending on the types of wafers, the configuration of equipment used differs, making it difficult to standardize the equipment, reducing costs and shortening delivery times through standardization. Couldn't hope.
(→ Equipment manufacturing productivity)
(2) The generation of semiconductor wafers is fast, and it is necessary to improve the function of the apparatus. However, the modification of the apparatus is not easy, and the cost of renewing the apparatus is great.
(→ Scalability)
(3) Since the polishing apparatus is usually installed in a clean room, it is necessary to suppress as much as possible the disassembly of equipment during repair and the exchange of parts, but there is a limit on the assembly structure of the apparatus. (→ Maintenance)
(4) Since the layout of the size of the apparatus, the loading / unloading position of the wafer cassette, the position of the operation panel, etc. is fixed, it is inconvenient to access the apparatus depending on the location of use. (→ user compatibility)

As one means for avoiding such a problem, it is conceivable to perform blocking for each function of the apparatus, and further arrange a control device for each block to adapt to the blocking of the apparatus.
However, making full use of the features of the block, and monitoring the state of the utility necessary for the operation of the apparatus, the abrasive liquid supply apparatus, waste liquid processing apparatus, which are also ancillary equipment essential for the operation of the apparatus, In some cases, it was necessary to construct a new system different from the conventional control system in order to optimally operate the entire apparatus by linking the cooling water supply apparatus and the hot water supply apparatus.

  By devising this new system, the present invention provides a polishing apparatus that is suitable for blocking the apparatus, has excellent productivity, expandability, maintainability, user-friendliness, and has high efficiency in cooperation with incidental equipment. With the goal.

In order to achieve the above object, a polishing apparatus of the present invention is a polishing apparatus for polishing a semiconductor wafer using an abrasive liquid, and the polishing apparatus is connected to an abrasive liquid supply apparatus, and the polishing apparatus is , Loading / unloading block, transfer block including a robot for moving a semiconductor wafer, polishing block including a rotary table and a top ring for polishing the semiconductor wafer, and a cleaning block including a cleaning tank for cleaning the polished semiconductor wafer And a control device is provided in each block, and each block can be mechanically installed and assembled in units of each block as a function-by-function block divided for each function of the polishing apparatus. The polishing apparatus further includes the load / unload block. A control block connected to each of a polishing block, a transport block, a polishing block, a cleaning block, and the abrasive liquid supply device, and the control block manages the load / unload block, the transport block, the polishing block, and the cleaning block Management software load / unload block management task, transport block management task, polishing block management task, cleaning block management task, and devices that control the control device of each block supported by each management task A control task , a utility monitoring task for monitoring the utility receiving state consisting of power, pure water, and compressed air necessary for the operation of the polishing apparatus, and an interlock for controlling the interlock between the abrasive fluid supply apparatus and the polishing apparatus Having control software, front Control block, the loading and unloading block, transport block, and controls the operation of the equipment of the polishing block and cleansing block by the management software in the device control tasks are supported on the respective management tasks is, the load The robot is instructed to take out the semiconductor wafer from the unload block and return the polished, cleaned and dried semiconductor wafer to the load / unload block, and the utility monitoring task monitors the receiving state of the utility. The interlock control software outputs a signal to a control device provided in the abrasive liquid supply device, and controls the operation of the polishing apparatus and the abrasive liquid supply device to be interlocked.

In one aspect of the present invention, the control block includes an electric terminal block that supplies electricity to the load / unload block, a conveyance block, a polishing block, and a cleaning block, a computer, and the load / unload block from the computer. A communication terminal block for sending a control signal to the transfer block, the polishing block, and the cleaning block, a power supply terminal block for receiving the supply of electricity from the outside, and an operation panel for commanding the operation of the polishing apparatus. Includes a driver that sends a driving current to the motor, an electric terminal block that receives electricity from the control block, a control valve that drives a valve in the cleaning block, and an air supply kit that supplies air to the control valve And an input that converts control signals to the driver and control valve. And over the face, and wherein the Rukoto to have a communication terminal block for receiving a control signal from the control block.

In one aspect of the present invention, the polishing apparatus is further connected to at least one of incidental facilities including a waste liquid treatment apparatus, a hot water supply apparatus, and a cooling water supply apparatus, and the control block of the polishing apparatus includes the interlock control software. Accordingly, the auxiliary equipment respectively outputs a signal to the provided control device, and controls to said Rukoto so as to interlock the operation of the ancillary equipment and the polishing apparatus.

  A preferred aspect of the present invention is a load / unload block that transfers a cassette containing a wafer, a transfer block that moves the wafer, a polishing block that polishes the wafer, a cleaning block that cleans the polished wafer, In a polishing apparatus comprising a control block for controlling the operation of the apparatus, the load / unload block, the transport block, the polishing block and the cleaning block are connected to the control block by a power line and a signal line, respectively, and control software is loaded to the load / unload It is configured for each of a load block, a conveyance block, a polishing block, and a cleaning block.

In a preferred aspect of the present invention, software for monitoring a utility is added to the control software.
In a preferred aspect of the present invention, the abrasive liquid supply device, the waste liquid treatment device, the cooling water supply device, and the hot water supply device are connected to the control block through a signal line.
In a preferred aspect of the present invention, software for controlling the interlocking between the polishing liquid supply device, the waste liquid treatment device, the cooling water supply device, and the hot water supply device and a polishing device is added to the control software.

  In the preferred embodiment of the present invention, since the load / unload block, the transport block, the polishing block and the cleaning block are connected to the control block by the power supply line and the signal line, respectively, the previous four blocks are mechanically, electrically Are installed and assembled in block units, and during operation, control operations are performed via the respective software by the control block.

In a preferred aspect of the present invention, utility monitoring software added to the control software monitors utility receiving conditions such as power, pure water, and compressed air necessary for operation of the apparatus.
In a preferred embodiment of the present invention, each of the abrasive liquid supply device, the waste liquid treatment device, the cooling water supply device, and the hot water supply device, which are ancillary facilities indispensable for the operation of the device, is generated by signals output from the control block. Be controlled.
In a preferred aspect of the present invention, the cooperative operation with the polishing apparatus is controlled by the interlock control software of the abrasive liquid supply device, waste liquid treatment device, cooling water supply device, and hot water supply device added to the control software. Is done.

According to the present invention having a configuration in which a control device is provided for each functional block, control of each block constituting the apparatus is performed on both hardware and software sides, so it is easy to deal with these options. Yes, the device blocking is completely achieved.
The control panel can be standardized, and at the same time, a preliminary operation check can be performed in units of blocks. This can reduce costs, shorten delivery times, improve reliability, and improve device manufacturing productivity.
In addition, even if there is a change in control due to a change in function, it is possible to cope with a change in the control device in the block and a minimum software change in the block, so the control panel can be used as it is. One expandability of future devices is also realized in control.

Further, it becomes possible to control the entire polishing apparatus including the utility and the attached device.
In addition, by introducing a wiring-saving system for communication, the amount of wiring can be greatly reduced, which is effective in reducing device production costs.
A polishing system including incidental equipment can be constructed in the polishing apparatus, and a control system that maximizes the polishing efficiency can be set.

Hereinafter, embodiments of a polishing apparatus according to the present invention will be described with reference to the drawings.
FIG. 1 is an external view of a polishing apparatus according to the present invention. The apparatus main body A is provided with a delivery port 3, and after a cassette 2 containing unpolished wafers 1 is inserted into the cassette delivery port 3, an operation panel is shown. When the switch 4 is turned on, the wafers 1 in the cassette 2 are automatically extracted one by one, polished, washed, returned to the original cassette 2 and stored. After all the wafers 1 have been polished, the cassette 2 is taken out and sent to the next process.

  FIG. 2 shows the inside of the apparatus main body A. A loading / unloading block 5 for transferring a cassette containing the wafer 1, a transfer block 6 for moving the wafer 1, and a polishing block 7 for polishing the wafer 1. A cleaning block 8 for cleaning the polished wafer 1 and a control block 9 for controlling each of these blocks are arranged independently on the common base 10.

  The load / unload block 5 includes a stage 11 on which the cassette 2 is placed, and a sensing sensor 12 that measures (wafer mapping) the number of stored wafers 1a to z and the positions of the storage shelves 13a to 13z. The information is stored in the computer 14 in the control block 9.

  A robot 15 is movably mounted on the transfer block 6 on a rail 6a, and the wafer 16a is transferred between the blocks by the fingers 16. The robot 15 functions as a unit, and a plurality of robots 15 can be installed on the rail 6a.

The polishing block 7 includes a rotary table 18 and a top ring 17 facing the rotary table 18. A polishing cloth is attached to the surface of the rotary table 18, and a device for supplying an abrasive liquid onto the polishing cloth surface is provided. It has been.
The cleaning block 8 includes a cleaning tank 19 for cleaning with pure water and a drying tank 20, and these tanks 19, 20 are units constituting the cleaning block 8.

  FIG. 3 shows a case where the chassis 21 containing the control device of the cleaning block 8 is pulled out as an example of the configuration of the block control unit. The chassis 21 includes a driver 22 that sends a driving current to the motor of the cleaning brush, an electric terminal block 23 that supplies electricity to the driver 22, an air cylinder that moves the cleaning brush onto the wafer 1 and cleaning pure water. A control valve 24 for driving a valve to be sent, an air supply kit 25 for supplying air to the control valve 24, an interface 27 for sending a control signal to the driver 22 and the control valve 24, and a communication terminal block 26 for receiving the control signal are attached. Yes.

FIG. 4 is a diagram showing the inside of the control block 9, and includes a power supply unit 28 and an electric terminal block 29 that supply electricity to each block, a computer 14 that issues a control command, a communication terminal block 30 that sends a control signal, A power supply terminal block 31 that accepts supply of electricity from the outside and an operation panel 4 that commands operation are provided.
The control device of the cleaning machine 8 is that the power source is a power line L between the electrical terminal block 23 of the cleaning machine and the electrical terminal block 29 of the control block 9, and the signal is the communication terminal block 26 of the cleaning machine and the control block. The communication terminal block 30 is connected by a communication line C.

  FIG. 5 is a diagram illustrating a hardware configuration of the control system. In each of the blocks 5 to 9, a power source is connected to a power source unit in the control panel, and a control device is connected to a computer 14 which is a main controller in the control panel by communication. The auxiliary equipment such as the abrasive liquid supply device 31, the waste liquid treatment device 32, the cooling water supply device 33, the hot water supply device 34, etc. have their own control devices, and commands for starting and stopping of these devices and failures. This communication is performed by exchanging signals with the computer 14 of the polishing apparatus.

  FIG. 6 is a diagram illustrating a software configuration of the control system. The system task 40 of the entire apparatus includes an operation panel task 41, management tasks 41 to 46 for each block, and a utility monitoring task 47. Each management task supports the device control tasks 42A to 46A of each block.

The operation of the polishing apparatus of the present invention configured as described above will be described.
1 is placed on the stage 11 of the load / unload block 5, and the number of wafers 1a-z and the positions of the storage shelves 13a-z measured by the sensing sensor 12 are measured. (Wafer mapping), and the information is stored in the computer 14 in the control block 9. When the mapping is completed, the fingers 16 of the robot 15 mounted on the transfer block 6 take out the wafer 1a in the shelf 13a of the cassette 2.

  The relative positions of the robot 15 and the cassette 2 are stored in the computer 14 in advance by teaching after the arrangement of each block. That is, the operation and position setting of the robot 15 is performed by a command from the computer 14, and the structure between the load / unload block 5 on which the cassette 2 is placed and the transport block 6 on which the robot 15 is mounted is structurally. It is not determined by the relationship between dimensions obtained by restraint.

  The wafer 1 a taken out from the cassette 2 is mounted on the top ring 17 of the polishing block 7 by the robot 15 and polished on the rotary table 18. A polishing cloth is affixed to the surface of the rotary table 18, and polishing is performed in a state in which the abrasive liquid flows down.

The polished wafer 1a is transferred to the cleaning block 8 by the robot 15 and mounted in the cleaning tank 19 in the block. When the cleaning is completed, the wafer 1a is mounted in the drying tank 20 in the same block, drained, and then removed from the cleaning block 8 by the robot 15 and returned to the storage shelf 13a of the cassette 2. The relative positions of the robot 15 and the cleaning block are stored in advance in the computer 14 as described above.
In this way, the polishing of one wafer 1a is completed, the remaining wafers 1b to 1z are subsequently polished, and the cassette is replaced when all the wafers have been processed.

  In this apparatus, for example, a cleaning tank 19 may be added to the cleaning block 8 in order to improve cleaning performance, or a robot 15 may be added to the transfer block 6 to increase throughput, and the block may be repaired. Sometimes removed. In this case, since the work for disassembly and repair is performed in a separate room by being moved by a dedicated carriage, dust generation at the device installation location is kept to a minimum. When such an update or replacement with an alternative block is performed, the relative position is determined by teaching.

  Here, the load / unload block 5, the transport block 6, the polishing block 7 and the cleaning block 8 are connected to the control block 9 by a power supply line and a signal line, respectively, and the previous four blocks are mechanically and electrically connected. Installation and assembly can be performed in units of blocks, and during operation, control operations are performed by the control block 9 via the management tasks 42 to 46, which are software, and the device control tasks 42A to 46A supported thereby.

In this apparatus, the utility monitoring task 47 monitors the receiving state of utilities required for operation of the apparatus, for example, power supply, pure water, compressed air, etc., and when these conditions change, measures corresponding thereto are taken. Is taken quickly.
Further, the abrasive liquid supply device 31, the waste liquid treatment device 32, the cooling water supply device 33, and the hot water supply device 34, which are auxiliary facilities indispensable for the operation of the device, are output by the signals output from the control block 9. The linked operation is controlled by the linked control software added to the control software via the control device of each device.

Process conditions for optimally polishing the wafer 1 include the rotational speed and pressing force of the top ring 17 according to the film to be polished on the surface of the wafer 1, the rotational speed of the rotary table 18 and the type of cloth material on the surface. There are types of abrasive liquids, and these are set and selected appropriately depending on the type of film on the wafer surface. Here, the chemical properties of the abrasive liquid vary greatly depending on the type. For example, when the wafer film is SiO ₂ , the abrasive liquid is nearly neutral, but when the film is a metal, it is acidic or alkaline. Therefore, a special material having corrosion resistance is used as a material of the polishing-related member that comes into contact with the abrasive fluid. Also, in the post-process cleaning, the mechanism of the cleaning device differs depending on the wafer film.

  Under such conditions, the present apparatus can be completely standardized for the load / unload block 5, the transport block 6 and the control block 9, and is stocked in a block. Since some parts of the polishing block 7 and the cleaning block 8 differ depending on the type of the wafer 1, they are assembled into a semi-finished product, and the parts are optionally stocked. Even in this case, since the control for each block constituting the apparatus is performed on both hardware and software sides, it is easy to cope with these options, and the blocking of the apparatus is completely achieved.

It is a perspective view which shows the external appearance of the polishing apparatus of one Example of this invention. (A) is a perspective view which shows the inside of the polishing apparatus of one Example of this invention, (b) is a figure which shows the structure of a cassette. It is a perspective view which shows the washing | cleaning block of the polishing apparatus of one Example of this invention. It is a perspective view which shows the control block of the polishing apparatus of one Example of this invention. It is a block diagram which shows the structure of the hardware of the control system of the polishing apparatus of one Example of this invention. It is a block diagram which shows the structure of the software of the control system of the polishing apparatus of one Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wafer 2 Cassette 3 Delivery port 4 Operation panel 5 Load / unload block 6 Transfer block 7 Polishing block 8 Cleaning block 9 Control block 10 Common base 11 Stage 12 Sensing sensor 13 Storage shelf 14 Computer 15 Robot 16 Finger 17 Top ring 18 Rotation Table 19 Cleaning tank 20 Drying tank 21 Chassis 22 Driver 23 Electric terminal block 24 Control valve 25 Air supply kit 26 Communication terminal block 27 Interface 28 Power supply unit 29 Electric terminal block 30 Communication terminal block 31 Abrasive liquid supply device 32 Waste liquid processing device 33 Cooling Water supply device 34 Hot water supply device L Power line C Communication line

Claims (3)

A polishing apparatus for polishing a semiconductor wafer using an abrasive liquid, wherein the polishing apparatus is connected to an abrasive liquid supply apparatus,
The polishing apparatus comprises:
Load / unload block,
A transport block including a robot for moving a semiconductor wafer;
A polishing block comprising a rotary table and a top ring for polishing a semiconductor wafer;
A cleaning block that includes a cleaning tank and cleans the polished semiconductor wafer;
A control device is provided in each block, and each block is configured so that it can be installed and assembled independently in units of blocks mechanically as a function-by-function block formed for each function of the polishing apparatus.
The polishing apparatus further includes a control block connected to each of the load / unload block, the conveyance block, the polishing block, the cleaning block, and the abrasive liquid supply device,
The control block includes a load / unload block management task, a transport block management task, a polishing block management task, and a cleaning block management task, which are management software for managing the load / unload block, the transport block, the polishing block, and the cleaning block. , A device control task that is supported by each management task and controls the control device of each block, and a utility receiving state consisting of a power source, pure water, and compressed air necessary for the operation of the polishing apparatus. Utility monitoring task for monitoring, and interlock control software for controlling the interlock between the abrasive fluid supply device and the polishing device,
The control block controls the operation of the load / unload block, transfer block, polishing block, and cleaning block devices by the device control task supported by each management task, which is the management software. The robot is instructed to take out the semiconductor wafer from the unload block and return the polished, cleaned and dried semiconductor wafer to the load / unload block, and monitor the utility receiving state by the utility monitoring task. A polishing apparatus, wherein the interlock control software outputs a signal to a control device provided in the abrasive liquid supply device, and controls the operation of the polishing apparatus and the abrasive liquid supply device to be interlocked. The control block includes an electric terminal block for supplying electricity to the load / unload block, transfer block, polishing block, and cleaning block, a computer, and the load / unload block, transfer block, polishing block from the computer, A communication terminal block for sending a control signal to the cleaning block, a power supply terminal block for receiving the supply of electricity from the outside, and an operation panel for commanding the operation of the polishing apparatus are provided.
The cleaning block supplies a drive current to a motor, an electric terminal block that receives electricity from the control block, a control valve that drives a valve in the cleaning block, and supplies air to the control valve The polishing apparatus according to claim 1, further comprising: an air supply kit; an interface that converts a control signal to the driver and the control valve; and a communication terminal block that receives the control signal from the control block.   The polishing apparatus is further connected to at least one of incidental equipment comprising a waste liquid treatment apparatus, a hot water supply apparatus, and a cooling water supply apparatus, and the control block of the polishing apparatus is connected to the auxiliary equipment by the interlock control software. The polishing apparatus according to claim 1 or 2, wherein a signal is output to a control device provided to control the operation of the polishing apparatus and the incidental equipment in conjunction with each other.

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