WO2020047942A1 - 一种化学机械平坦化设备 - Google Patents

一种化学机械平坦化设备 Download PDF

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Publication number
WO2020047942A1
WO2020047942A1 PCT/CN2018/110052 CN2018110052W WO2020047942A1 WO 2020047942 A1 WO2020047942 A1 WO 2020047942A1 CN 2018110052 W CN2018110052 W CN 2018110052W WO 2020047942 A1 WO2020047942 A1 WO 2020047942A1
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Prior art keywords
polishing
wafer
loading
unloading
chemical mechanical
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PCT/CN2018/110052
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English (en)
French (fr)
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顾海洋
张志军
古枫
王东辉
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杭州众硅电子科技有限公司
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Publication of WO2020047942A1 publication Critical patent/WO2020047942A1/zh

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B29/00—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents
    • B24B29/02—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00—Component parts such as frames, beds, carriages, headstocks
    • B24B41/005—Feeding or manipulating devices specially adapted to grinding machines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00—Component parts such as frames, beds, carriages, headstocks
    • B24B41/06—Work supports, e.g. adjustable steadies

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  • the invention belongs to the technical field of grinding or polishing devices, and particularly relates to a chemical mechanical planarization device used in the manufacturing process of a semiconductor integrated circuit chip.
  • Chemical mechanical polishing (Chemical Mechanical Planarization, CMP) technology is a combination of chemical and mechanical effects. Its working principle is: first, the surface material of the workpiece chemically reacts with the oxidant and catalyst in the polishing liquid to form a soft layer that is relatively easy to remove, and then the softness of the abrasive and polishing pad in the polishing liquid removes the soft layer The surface layer of the workpiece is exposed again, and then a chemical reaction is performed to complete the polishing of the surface of the workpiece in the alternating process of chemical and mechanical processes.
  • chemical mechanical polishing technology has been developed into a combination of on-line measurement, online endpoint detection, cleaning and other technologies of chemical mechanical polishing technology is the integrated circuit to the miniaturization, multilayering, thinning, flattening process development products. At the same time, it is also a process technology necessary for the wafer to transition from 200mm to 300mm or even larger diameters, improve productivity, reduce manufacturing costs, and globally planarize the substrate.
  • a typical chemical mechanical planarization equipment usually includes multiple polishing units and auxiliary devices such as cleaning, wafer transport, and drying.
  • the polishing unit usually includes a table, a polishing disk, a polishing head, a polishing arm, a dresser, a polishing liquid arm, etc.
  • the polishing disk, a polishing head, a polishing arm, a dresser, and a polishing liquid arm are arranged on the table according to the processing position.
  • the spatial arrangement of the polishing unit and modules such as cleaning and wafer transportation has a great impact on the overall polishing throughput of the chemical mechanical planarization equipment.
  • the transfer of wafers between the polishing unit and the outside and between the polishing unit is usually achieved by the loading and unloading table or a device that plays a similar role.
  • the industry has already developed a mature model, such as the patent number is
  • the transfer station functioning as a loading and unloading station and the three polishing units have a square layout.
  • a carousel with four square-shaped polishing heads and a rotatable device moves downwards, and sequentially loads and unloads wafers with the loading and unloading table.
  • the three polishing units have a cleaning device, which is located adjacent to the polishing unit, and one of them is located between the corresponding polishing unit and the loading and unloading table.
  • a loading and unloading station needs to provide loading and unloading services for three polishing units by means of a common carousel, the disadvantage of this technical layout is that the process is complicated.
  • Another US patent US8795032B2 discloses another layout, in which four polishing units are arranged side by side, and wafer transfer is completed by a loading and unloading area at the end of the planarization device and two linear transport mechanisms arranged along the arrangement direction of the polishing unit. The other side of the linear transport mechanism is a cleaning area.
  • Each of the above-mentioned linear transport mechanisms provides services for two polishing units, and sets two transfer stations for each polishing unit.
  • the polishing head of the polishing unit can load and unload wafers from one of the transfer stations.
  • This layout uses a linear arrangement of polishing units, but its disadvantage is that although each polishing unit is provided with two transfer stations, the polishing unit directly loads and unloads wafers from only one of them during the polishing process, so from the perspective of wafer transfer efficiency There is still room for improvement.
  • the purpose of the present invention is to propose a new type of chemical mechanical planarization device for polishing unit array layout based on the problems of low wafer transfer efficiency and complicated transfer mechanism structure in existing chemical mechanical planarization devices, and to propose a new polishing unit array layout based on the array layout.
  • Wafer transfer module The module is arranged above the polishing unit array, so the wafer transfer unit of the wafer transfer module can pass through the polishing unit at any time without interference.
  • the technical solution adopted by the present invention is a chemical mechanical planarization device, which includes a polishing module, a cleaning unit, and a wafer transfer module.
  • the cleaning unit cleans the polished wafer.
  • the polishing module includes two columns of polishing unit arrays, each column of polishing units includes two or more groups of polishing units, and the loading and unloading tables corresponding to the two columns of polishing unit arrays are longitudinally arranged in the column direction of the polishing unit array, and the wafer is transported.
  • the working part of the module is located vertically above the loading and unloading tables arranged in the longitudinal direction, and completes the transfer of wafers between other loading and unloading areas, the loading and unloading tables, and the loading and unloading tables.
  • the other loading and unloading areas described above are transfer stations, and wafers entering and exiting the polishing unit are temporarily stored through the transfer station.
  • the cleaning units are arranged in two rows corresponding to two rows of polishing unit arrays.
  • the above-mentioned wafer transfer module includes one or more sets of wafer transfer units, and each set of wafer transfer units includes a guide device that moves in a horizontal direction, a horizontal movement driving device, a vertical movement mechanism, a wafer chuck, and a wafer card.
  • the claw, the horizontal movement driving device can slide along the guide device, the vertical movement mechanism can work in two modes of high position and low position.
  • the wafer claw is installed on the wafer chuck, which can be opened and closed.
  • each of the above-mentioned multiple sets of wafer transfer units forms a cascade along the column direction of the two columns of polishing units to complete the wafer in other loading and unloading areas, such as a transfer table, With each loading and unloading station and each loading and unloading station.
  • the above-mentioned multiple sets of wafer transfer units can cooperate with each other to realize wafer flow in the entire polishing unit array.
  • the wafer chuck is a flip structure, and two sets of wafer claw mechanisms are arranged on both sides thereof.
  • the above cleaning module is equipped with a robot or a similar automatic device, and can transfer wafers between the polishing unit and the cleaning unit, and the wafers are transferred through a transfer table.
  • the above loading and unloading table can be moved longitudinally in the column direction of the polishing unit array.
  • Such a loading and unloading table can correspond to more than one polishing unit.
  • only three loading and unloading tables can correspond to six polishing. unit.
  • the above-mentioned chemical mechanical planarization equipment may integrate an equipment front-end unit module (EFEM) during operation.
  • EFEM equipment front-end unit module
  • the cleaning unit may choose to use megasonic cleaning or roller brush cleaning, and may also have a wafer drying function.
  • a polishing door that can be opened and closed is set between the polishing unit and the loading and unloading table.
  • the invention further proposes a method for wafer transfer using the chemical mechanical planarization equipment, which specifically includes the following steps:
  • the present invention Compared with the existing chemical mechanical planarization equipment technology, the present invention has the following beneficial technical effects:
  • the layout in which the polishing units are arranged in two rows and the wafer transfer unit is centered helps reduce the transfer stroke.
  • the processing efficiency of the chemical mechanical planarization equipment is increased by about 50% year-on-year.
  • the wafer transfer unit above the loading and unloading station can transfer wafers from one loading and unloading station to another loading or unloading station, or take wafers in or out of the polishing unit, the wafer transfer unit Above, so when the polishing head is loading or unloading the wafer at the loading and unloading station, the wafer transfer unit can pass through the polishing unit at any time without interference;
  • the cleaning units arranged left and right can choose to place the wafer in any cleaning unit through the cleaning robot, resulting in the efficiency of the polishing and cleaning combined unit being improved;
  • the wafer transfer unit can be two or more sets to meet the needs of two rows of multiple polishing unit arrays, and the equipment has good scalability.
  • FIG. 1 is a top view of a chemical mechanical planarization device (2 ⁇ 3 array) according to the present invention
  • FIG. 2 is a perspective view of the chemical mechanical planarization device shown in FIG. 1;
  • FIG. 3 is a schematic structural diagram of a polishing unit
  • FIG. 4 is a schematic structural diagram of a wafer transfer unit according to the present invention.
  • FIG. 5 is a perspective view of an embodiment having a dual wafer transfer unit
  • FIG. 6 is a perspective view of an embodiment with a movable loading and unloading platform.
  • a chemical mechanical planarization apparatus includes a plurality of polishing units and a plurality of cleaning units.
  • the polishing unit includes a table, a polishing disk, a polishing head, a polishing arm, a dresser, a polishing liquid arm, a loading and unloading table, and the like.
  • the polishing disc, the polishing head, the polishing arm, the dresser, and the polishing liquid arm are arranged on a workbench according to a processing position.
  • the polishing arm can carry a polishing head to move between the polishing disc and the loading and unloading table.
  • the dresser grinds the polishing disc with a certain pressure on the polishing disc.
  • the polishing liquid arm can provide the chemical liquid required for polishing.
  • the polishing door of the polishing unit When the wafer needs to be loaded or unloaded, the polishing door of the polishing unit is opened, and the polishing arm rotates the polishing head to the loading and unloading table position. After the wafer is loaded and unloaded, the polishing arm carries the polishing head to the polishing disk position for polishing. At this time, the polishing door is closed to prevent leakage of liquid and water vapor in the polishing area.
  • the polishing liquid arm flows out of the polishing liquid, and the dresser performs the dressing work on the polishing disc. The polishing disc rotates at a certain speed, and the polishing head rotates at a certain speed at the same time.
  • a cleaning unit is connected to the polishing unit array.
  • the cleaning units are arranged in two or more rows to form a polishing and cleaning unit.
  • a transfer station is installed at the interface between the polishing unit array and the cleaning unit, and wafers entering and leaving the polishing unit are temporarily stored through the transfer station.
  • a robot is installed in the cleaning unit to transfer the wafer between the polishing unit and the cleaning unit.
  • the wafer is transported through a transfer station.
  • the chemical mechanical planarization apparatus of the present invention generally also integrates an equipment front-end unit module (EFEM).
  • EFEM equipment front-end unit module
  • the cleaning unit generally includes megasonic cleaning, roller brush cleaning, wafer drying, and the like.
  • the polishing module is a polishing unit array composed of two columns and multiple sets of polishing units. All the loading and unloading tables of the two columns and multiple sets of polishing units are arranged longitudinally in the column direction of the two columns of polishing units.
  • the polishing unit array is also Can be expanded to 2 columns and multiple groups. In order to facilitate the introduction of the principles of the present invention and the implementation of the present invention by those skilled in the art, the following descriptions of the embodiments are based on the layout of 2 columns and 3 groups, and are hereby described.
  • Figures 1 and 2 respectively show a top view and a perspective view of a (2 ⁇ 3 array) chemical mechanical planarization device.
  • the chemical mechanical planarization device includes a polishing unit array 100, a cleaning unit combination 200, and a wafer transfer unit 120.
  • the polishing unit array 100 is composed of two columns and three rows of polishing units 110.
  • Each group of polishing units 110 includes, as shown in FIG. 3, a table 115, a polishing disc 117, a polishing head 112, a polishing arm 111, a dresser 114, a polishing liquid arm 113, a loading and unloading table 116, a polishing door 119, and the like.
  • a polishing door 119 is provided between the polishing unit 110 and the loading and unloading table 116.
  • the polishing door 119 of the polishing unit 110 is opened, and the polishing arm 111 carries the polishing head 112 to the position of the loading and unloading table 116.
  • the polishing arm 111 rotates the polishing head 112 to the position of the polishing disk 117 for polishing.
  • the polishing door 119 is closed to prevent leakage of liquid and water vapor in the polishing area.
  • the wafers that need to be chemically mechanically polished enter the polishing unit array 100 through the transfer table 118 or other areas that serve as temporary wafer loading and unloading areas.
  • the chemically mechanically polished wafers leave the polishing unit array 100 through the transfer table 118.
  • the wafer transfer between the transfer station 118 and each loading and unloading station 116 and the wafer transfer between each loading and unloading station 116 are completed by the wafer transfer unit 120.
  • a polishing disc 117, a polishing head 112, a polishing arm 111, a dresser 114, and a polishing liquid arm 113 are disposed on a table 115.
  • the polishing disc 117 is connected to the table 115 through a bearing system, and the polishing disc 117 can be continuously rotated.
  • the polishing arm 111 can carry the polishing head 112 between the polishing disc 117 and the loading and unloading table 116. During the polishing process, the polishing arm 111 carries the polishing head 112 slightly swinging within the range of the polishing disc 117.
  • the dresser 114 reciprocates within the radius of the polishing disc 117, and the on-line dressing of the polishing disc 117 is realized by the rotating grinding wheel on the head of the dresser 114.
  • the polishing liquid arm 113 supplies polishing liquid on the polishing disc 117.
  • the polishing arm 113 rotates the polishing head 112 to the position of the loading and unloading table 116 to unload the wafer. After the wafer is unloaded, another wafer is reloaded for the next polishing cycle.
  • FIG. 4 is a schematic diagram of a wafer transfer unit 120 as a core component of a wafer transfer module, including: a guide device 121 moving in a horizontal direction, a horizontal movement driving device 122, a vertical movement mechanism 123, and a wafer chuck 124 , Wafer claw 125 and so on.
  • This part is the working part of the wafer transfer module, which is connected to the chemical mechanical planarization equipment through the connection part (not shown) of the wafer transfer module.
  • the vertical movement mechanism 123 In the initial state, the vertical movement mechanism 123 is at a high position, so that the wafer chuck 124 can walk freely in the horizontal direction.
  • the vertical movement mechanism 123 When the guiding device 121 runs above the transfer table 118 or the loading and unloading table 116, the vertical movement mechanism 123 is lowered to a low position, and the wafer chuck 124 is provided with a wafer claw 125 that can be opened and closed. Wafer claw 125. After the wafer is picked up and placed at the low position of the vertical movement mechanism 123, the vertical movement mechanism 123 rises to the high position, and the horizontal movement driving device 122 runs to the next transfer table 118 or the loading and unloading table 116.
  • the vertical movement mechanism 123 drops to a low position, and the wafer claw 125 on the wafer chuck 124 performs a wafer picking operation.
  • Such reciprocating motion enables the wafer to be transferred between the transfer table 118 and each loading and unloading table 116.
  • the wafer chuck 124 in the wafer transfer unit 120 is designed as a flip structure, and two sets of wafer claw 125 mechanisms are arranged on both sides of the wafer chuck 124. At this time, the example can effectively reduce the walking route of the wafer transfer unit 120 and increase the transfer capacity of the wafer transfer unit 120.
  • the wafer transfer unit above the loading and unloading stage can transfer wafers from one loading and unloading stage to another, or take wafers in or out of the polishing unit, because the wafer transfer unit is arranged above the loading and unloading stage Therefore, when the polishing head is loading or unloading the wafer at the loading and unloading station, the wafer transfer unit can pass through the polishing unit at any time without being disturbed, which constitutes one of the most important advantages of the present invention.
  • the wafer after chemical mechanical polishing is placed on the transfer table 118 by the wafer transfer unit 120, and the wafer is transferred from the transfer table 118 to the cleaning unit 200 by the robot of the cleaning unit 200 for polishing. Cleaning and drying.
  • the cleaning unit 200 is arranged on the left and right. According to requirements, the cleaning robot can choose to place the wafer in any one of the cleaning units 200.
  • the wafer transfer unit 120 may be designed in two or more sets, and a cascade is formed in the column direction of the two rows of polishing units to meet the production capacity requirements of the two rows of multiple polishing unit arrays 100 .
  • the transfer of the wafer is realized by the transfer unit 120 a and the transfer unit 120 b in cooperation.
  • the transfer unit 120a is responsible for transferring wafers between the transfer station 118, the loading and unloading station 116f, the loading and unloading station 116e, and the loading and unloading station 116d.
  • the transfer unit 120b is responsible for the wafers at the loading and unloading station 116d, loading and unloading station 116c, loading and unloading station 116b, and loading and unloading station 116a Transfer.
  • the transfer unit 120a and the transfer unit 120b can reach the position of the loading and unloading table 116d at different times, so as to realize the circulation of the wafer in the entire polishing unit array 100.
  • a (2 ⁇ 3 array) chemical mechanical planarization device is provided with three movable loading and unloading tables, which are a loading and unloading table 116 a, a loading and unloading table 116 b, and a loading and unloading table 116 c.
  • the loading and unloading station 116a is responsible for the polishing unit 110a and the polishing unit 110b; the loading and unloading station 116b is responsible for the polishing unit 110c and the polishing unit 110d; the loading and unloading station 116c is responsible for the polishing unit 110e and the polishing unit 110f.
  • the present invention adopts a layout in which the polishing units are arranged in two or more rows and the wafer transfer unit is centered to help reduce the transfer stroke.
  • the processing efficiency of the chemical mechanical planarization equipment is greatly improved year-on-year.
  • the overall layout is more flexible and adaptable.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • Disintegrating Or Milling (AREA)
  • Container, Conveyance, Adherence, Positioning, Of Wafer (AREA)

Abstract

一种化学机械平坦化设备，包括抛光模块、清洗单元（200）和晶圆传输模块，抛光模块包含两列抛光单元阵列（100），每列抛光单元阵列（100）包含多组抛光单元（110），两列抛光单元阵列（100）对应的装卸台（116）在位于抛光单元阵列（100）的列方向上纵向排列，晶圆传输模块的工作部晶圆传输单元（120）位于装卸台（116）的垂直上方，完成晶圆在其他装卸区与所述装卸台（116）以及所述装卸台（116）之间的传输。由于晶圆传输单元（120）布置在装卸台（116）的上方，抛光头在装卸台（116）进行装载或卸载晶圆时，晶圆传输单元（120）可以随时穿越抛光单元（110）而不会受到干扰，采用这种布局有助于减少传输的行程，使得化学机械平坦化设备的加工效率同比显著提升。

Description

一种化学机械平坦化设备 技术领域
本发明属于磨削或抛光装置技术领域，具体涉及一种半导体集成电路芯片制造过程中使用的化学机械平坦化设备。
背景技术
随着半导体行业的飞速发展,集成电路特征尺寸不断趋于微细化,因此半导体薄膜表面的高平坦化对器件的高性能、低成本、高成品率有着重要的影响。
化学机械抛光(Chemical Mechanical Planarization,CMP)技术是化学作用和机械作用相结合的技术。其工作原理是，首先工件表面材料与抛光液中的氧化剂、催化剂等发生化学反应，生成一层相对容易去除的软质层,然后在抛光液中的磨料和抛光垫的机械作用下去除该软质层,使工件表面重新裸露出来，随后再进行化学反应,藉此在化学作用过程和机械作用过程的交替进行中完成工件表面抛光。
目前，化学机械抛光技术已经发展成集在线量测、在线终点检测、清洗等技术于一体的化学机械抛光技术是集成电路向微细化、多层化、薄型化、平坦化工艺发展的产物。同时也是晶圆由200mm向300mm乃至更大直径过渡、提高生产率、降低制造成本、衬底全局平坦化所必需的工艺技术。
一个典型的化学机械平坦化设备通常包括多个抛光单元以及清洗、晶圆运输、干燥等辅助装置。抛光单元通常包括工作台、抛光盘、抛光头、抛光臂、修整器、抛光液臂等，抛光盘、抛光头、抛光臂、修整器、抛光液臂按照工艺加工位置布置在工作台上。实际的晶圆加工过程中发现，抛光单元与清洗、晶圆运输等模块的空间布置对于化学机械平坦化设备整体的抛光产出(throughput)有极大的影响。晶圆在抛光单元与外部以及在抛光单元之间的传输通常依靠装卸台或起类似作用的装置来实现，关于装卸台与抛光单元的空间布局，业界已经有比较成熟的模式，如专利号为US5738574的美国专利文献披露的技术方案中，其装卸台作用的transfer station与三个抛光单元为正方形布局。工作时，一个带有四个呈正方形分布抛光头的、且可以旋转的装置(carousel)向下运动，依次与装卸台完成晶圆的装卸。值得一提的是，上述装置中，三个抛光单元自带一个清洗装置，位置上与抛光单元近邻，其中一个位于对应的抛光单元与装卸台之间。很明显，由于一个装卸台需要借助一个共用的carousel给三个抛光单元提供装卸服务，因此这种技术布局的缺点是工艺过程复杂。另一件美国专利 US8795032B2公开了另一种布局，其中的四个抛光单元并排排列，晶圆传输由位于平坦化设备端部的装卸区和沿抛光单元排列方向设置的两个线性运输机构完成，线性运输机构的另一侧为清洗区。上述每一个线性运输机构为两个抛光单元提供服务，并为每个抛光单元设置两个传输工位，抛光单元的抛光头可以从其中一个传输工位装卸晶圆。这种布局采用了抛光单元的直线排列，但其缺点是每个抛光单元虽然设置两个传输工位，但抛光过程中抛光单元只从其中一个直接装卸晶圆，因此从晶圆传输效率的角度说还有需要改进的空间。
发明内容
本发明目的在于针对现有化学机械平坦化设备中存在的晶圆传输效率低、传输机构结构复杂的问题提出一种新型抛光单元阵列布局的化学机械平坦化设备，并基于该阵列布局提出一种晶圆传输模块，该模块设置在抛光单元阵列的上方，因此晶圆传输模块的晶圆传输单元可以随时穿越抛光单元而不会受到干扰。
为实现上述目的，本发明采用的技术方案为一种化学机械平坦化设备，包括抛光模块、清洗单元和晶圆传输模块，清洗单元对抛光后的晶圆进行清洗。所述抛光模块包含两列抛光单元阵列，每列抛光单元包含两组或多组抛光单元，两列抛光单元阵列对应的装卸台在位于抛光单元阵列的列方向上纵向排列，所述晶圆传输模块的工作部位于沿纵向排列的装卸台的垂直上方，完成晶圆在其他装卸区与所述装卸台以及所述装卸台之间的传输。
上述其他装卸区为转载台，进出抛光单元的晶圆要经过转载台暂存。
上述清洗单元排成两列对应两列抛光单元阵列。
进一步，上述晶圆传输模块包括一组或多组晶圆传输单元，每组晶圆传输单元包括在水平方向移动的导向装置、水平运动驱动装置、垂直运动机构、晶圆卡盘和晶圆卡爪，水平运动驱动装置可以沿导向装置滑动，垂直运动机构可以在高位和低位两个模式下工作，晶圆卡爪安装于晶圆卡盘上，可以做张开和闭合操作。
如果抛光单元阵列的行数较多，上述多组晶圆传输单元中的每组晶圆传输单元沿两列抛光单元的列方向上形成级联，完成晶圆在其他装卸区，如转载台，与各个装卸台以及各个装卸台之间的传输。
作为本发明晶圆传输模块的重要优点之一，上述多组晶圆传输单元可以互相协作，实现晶圆在整个抛光单元阵列中的流转。
作为优选，上述晶圆卡盘为翻转结构，在其两面布置两套晶圆卡爪机构。
上述清洗模块中装有机械手或类似自动装置，可以将晶圆在抛光单元和清洗单元之间传输，晶圆传输时要经过转载台。
上述装卸台可在抛光单元阵列的列方向上纵向移动，这样一个装卸台可以对应一个以上的抛光单元，如在2列X3组的布局中，只需3个装卸台来就可以对应6个抛光单元。
作为优选，上述化学机械平坦化设备在工作时可以集成设备前端单元模块(Equipment Front End Module，EFEM)。
作为优选，清洗单元可以选择采用兆声波清洗或滚刷刷洗，也可以带晶圆干燥功能。
为防止抛光区的液体和水汽外泄，抛光单元与装卸台之间设置可开启闭合的抛光门。
本发明还进一步提出一种利用上述化学机械平坦化设备进行晶圆传输的方法，具体包含以下步骤：
S1：在初始状态下，垂直运动机构处于高位，使得晶圆卡盘可以沿着水平方向自由行走；
S2：当导向装置运行到转载台或者装卸台的上方时，垂直运动机构下降到低位，晶圆卡盘上安装的晶圆卡爪抓取晶圆；
S3：随后垂直运动机构上升到高位，水平运动驱动装置运行到下一个转载台或者装卸台的上方；
S4：垂直运动机构下降到低位，晶圆卡盘上的晶圆卡爪进行释放晶圆操作；
S5：重复以上步骤，使得晶圆可以在转载台和各个装卸台之间实现传递。
与现有化学机械平坦化设备技术相比，本发明具有以下有益技术效果：
1，本发明中采用抛光单元排成两列、晶圆传输单元居中的布局有助于减少传输的行程，化学机械平坦化设备加工效率同比提升约50％，而且通过采用模块化的布局，设备布局更灵活；
2，因为装卸台上方的晶圆传输单元可以将晶圆从一个装卸台转移到另一个装卸台，或者将晶圆从抛光单元拿进或者拿出，晶圆传输单元因为布置在所述装卸台的上方，所以抛光头在装卸台进行装载或者卸载晶圆时，晶圆传输单元可以随时穿越抛光 单元而不会受到干扰；
3，与上述抛光单元与晶圆传输单元的布局相对应，左右布置的清洗单元通过清洗机械手可以选择将晶圆放至任一个清洗单元，导致抛光加清洗组合单元的效率也得到提升；
4，根据产能需要，晶圆传输单元可以为两套或者两套以上，以满足2列多组抛光单元阵列的需要，设备的可伸缩性较好。
附图说明
图1为本发明化学机械平坦化设备(2×3阵列)的俯视图；
图2为图1所示化学机械平坦化设备的立体效果图；
图3为一个抛光单元的结构示意图；
图4为本发明的晶圆传输单元的结构示意图；
图5为一个具有双晶圆传输单元的实施例的立体效果图；
图6为一个具有可移动装卸台的实施例的立体效果图。
具体实施方式
下面结合附图对本发明作进一步详细的说明。
根据本发明的化学机械平坦化设备，包括多个抛光单元和多个清洗单元。所述抛光单元包括工作台、抛光盘、抛光头、抛光臂、修整器、抛光液臂、装卸台等。所述抛光盘、抛光头、抛光臂、修整器、抛光液臂按照工艺加工位置布置在工作台上。所述抛光臂可以携带抛光头在抛光盘与装卸台之间运动。所述修整器在抛光盘上以一定的压力修磨抛光盘。所述抛光液臂可以提供抛光所需要的化学药液。需要装载或者卸载晶圆时，抛光单元的抛光门打开，抛光臂携带抛光头旋转至装卸台位置。装卸晶圆结束后，抛光臂携带抛光头旋转至抛光盘位置进行抛光加工。这时抛光门闭合，防止抛光区液体和水汽外泄。在抛光加工过程中，抛光液臂流出抛光液，修整器对抛光盘进行修整工作。所述抛光盘以一定的速度旋转，所述抛光头同时以一定的速度自转。
跟所述抛光单元阵列连接有清洗单元。所属清洗单元排成两列或多列，构成抛光加清洗组合单元。在抛光单元阵列和清洗单元衔接处装有转载台，进出抛光单元的晶圆都要经过转载台暂存。
所述清洗单元中间装有机械手，可以将将晶圆在抛光单元和清洗单元之间传输。晶圆传输时要经过转载台。
另外，本发明的化学机械平坦化设备一般还集成设备前端单元模块(EFEM)。清洗单元一般包括兆声波清洗、滚刷刷洗、晶圆干燥等。
本发明中，抛光模块为两列多组抛光单元组成的抛光单元阵列，两列多组抛光单元的所有装卸台在两列抛光单元的列方向纵向排列，但根据实际的需要，抛光单元阵列也可以扩展到2列多组。为便于介绍本发明的原理和本领域的技术人员实施本发明，以下的实施例说明都是基于2列3组的布局展开，特此说明。
图1、2所示分别为一个(2×3阵列)的化学机械平坦化设备俯视图和立体图，化学机械平坦化设备包括：抛光单元阵列100、清洗单元组合200和晶圆传输单元120。所述抛光单元阵列100由2列3行抛光单元110组合而成。
每一组抛光单元110包括，如图3所示，工作台115、抛光盘117、抛光头112、抛光臂111、修整器114、抛光液臂113、装卸台116、抛光门119等。
在抛光单元110与装卸台116之间设置抛光门119，需要装载或者卸载晶圆时，抛光单元110的抛光门119打开，抛光臂111携带抛光头112旋转至装卸台116位置。装卸晶圆结束后，抛光臂111携带抛光头112旋转至抛光盘117位置进行抛光加工。这时抛光门119闭合，防止抛光区液体和水汽外泄。需要进行化学机械抛光的晶圆，通过转载台118或其他起类似晶圆临时装卸区作用的区域进入抛光单元阵列100，化学机械抛光后的晶圆通过转载台118离开抛光单元阵列100。晶圆在转载台118与各个装卸台116之间的传输，以及晶圆在各个装卸台116之间的传输，通过晶圆传输单元120完成。
如图3所示，抛光盘117、抛光头112、抛光臂111、修整器114、抛光液臂113设置在工作台115上。抛光盘117通过轴承系统与工作台115连接，抛光盘117可以连续旋转。所述抛光臂111可以携带抛光头112在抛光盘117与装卸台116之间运动。在抛光过程中抛光臂111携带抛光头112在抛光盘117的范围内小幅摆动。在抛光过程中修整器114在抛光盘117的半径范围内往复运动，通过修整器114头部的旋转砂轮实现对抛光盘117的在线修整。在抛光过程中抛光液臂113会供给抛光液在在抛光盘117上。晶圆抛光结束后，抛光臂113携带抛光头112旋转至装卸台116的位置进行卸载晶圆，晶圆卸载后再重新装载另一片晶圆，进行下一个抛光循环。
如图4所示为作为晶圆传输模块的核心部件的晶圆传输单元120的示意图，包括：在水平方向移动的导向装置121，水平运动驱动装置122，垂直运动机构123，晶圆卡 盘124，晶圆卡爪125等。这部分为晶圆传输模块的工作部，其通过晶圆传输模块的连接部(图中未示出)与化学机械平坦化设备连接。
在初始状态下，垂直运动机构123处于高位，使得晶圆卡盘124可以沿着水平方向自由行走。当导向装置121运行到转载台118或者装卸台116的上方时，垂直运动机构123下降到低位，晶圆卡盘124上装有可以张开和闭合的晶圆卡爪125。晶圆卡爪125，在垂直运动机构123的低位取放晶圆结束后，垂直运动机构123上升到高位，水平运动驱动装置122运行到下一个转载台118或者装卸台116的上方，垂直运动机构123下降到低位，晶圆卡盘124上的晶圆卡爪125进行取放晶圆操作。如此往复运动，使得晶圆可以在转载台118和各个装卸台116之间实现传递。为了提高晶圆的传输效率，如图4所示，晶圆传输单元120中的晶圆卡盘124设计成翻转结构，在晶圆卡盘124的两面布置两套晶圆卡爪125机构。此时实例可以有效减少晶圆传输单元120的行走路线，增加晶圆传输单元120的传输能力。因为装卸台上方的晶圆传输单元可以将晶圆从一个装卸台转移到另一个装卸台，或者将晶圆从抛光单元拿进或者拿出，因为晶圆传输单元布置在所述装卸台的上方，所以抛光头在装卸台进行装载或者卸载晶圆时，晶圆传输单元可以随时穿越抛光单元而不会受到干扰，构成本发明的最主要优点之一。
如图1所示，经过化学机械抛光后的晶圆，被晶圆传输单元120放在转载台118上，由清洗单元200的机械手将晶圆从转载台118上转移到清洗单元200进行抛光后的清洗及干燥处理。所述清洗单元200布置左右两个，根据需要，清洗机械手可以选择将晶圆放至任一个清洗单元200。
作为本发明另一个实施例，晶圆传输单元120可以设计成两套或者两套以上，在沿两列抛光单元的列方向上形成级联，以满足2列多组抛光单元阵列100的产能需要。
如图5所示，晶圆的传输由传输单元120a和传输单元120b协同实现。传输单元120a负责晶圆在转载台118、装卸台116f、装卸台116e、装卸台116d之间的传输，传输单元120b负责晶圆在装卸台116d、装卸台116c、装卸台116b、装卸台116a之间传输。传输单元120a和传输单元120b可以在不同的时间到达装卸台116d的位置，以实现晶圆在整个抛光单元阵列100中的流转。
作为又一个实施例，如图6所示，一个(2×3阵列)的化学机械平坦化设备设置3个可移动的装卸台，分别为装卸台116a、装卸台116b、装卸台116c。装卸台116a 负责抛光单元110a和抛光单元110b；装卸台116b负责抛光单元110c和抛光单元110d；装卸台116c负责抛光单元110e和抛光单元110f。
上述最后两个实施例集中体现了本发明的晶圆传输单元配置的灵活性，以及晶圆传输单元与所服务的装卸台的配对时的灵活性，属于本发明的显著优点之一。
本发明中采用抛光单元排成两列或多列、晶圆传输单元居中的布局有助于减少传输的行程，化学机械平坦化设备加工效率同比大幅提升，而且通过采用模块化的布局，设备的整体布局更加灵活，适应性也更强。
以上具体实施方式的描述并不用以限制本发明，凡在本发明的精神和原则之内所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (13)

  1. 一种化学机械平坦化设备，包括抛光模块、清洗单元和晶圆传输模块，清洗单元对抛光后的晶圆进行清洗，其特征在于，所述抛光模块包含两列抛光单元阵列，每列抛光单元包含两组或多组抛光单元，两列抛光单元阵列对应的装卸台在位于抛光单元阵列的列方向上纵向排列，所述晶圆传输模块的工作部位于沿纵向排列的装卸台的垂直上方，完成晶圆在其他装卸区与所述装卸台以及所述装卸台之间的传输。
  2. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述其他装卸区为转载台，进出抛光单元的晶圆要经过转载台暂存。
  3. 根据权利要求1所述的化学机械平坦化设备，其特征在于，所述清洗单元排成两列，对应两列抛光单元阵列。
  4. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述晶圆传输模块包括一组或多组晶圆传输单元，每组晶圆传输单元包括在水平方向移动的导向装置(121)、水平运动驱动装置(122)、垂直运动机构(123)、晶圆卡盘(124)和晶圆卡爪(125)，水平运动驱动装置(122)可以沿导向装置(121)滑动，垂直运动机构(123)可以在高位和低位两个模式下工作，晶圆卡爪(125)安装于晶圆卡盘(124)上，可以做张开和闭合操作。
  5. 根据权利要求4所述的化学机械平坦化设备，其特征在于所述多组晶圆传输单元中的每组晶圆传输单元沿两列抛光单元的列方向上形成级联，完成晶圆在其他装卸区与各个装卸台以及各个装卸台之间的传输。
  6. 根据权利要求5所述的化学机械平坦化设备，其特征在于所述多组晶圆传输单元互相协作，实现晶圆在整个抛光单元阵列中的流转。
  7. 根据权利要求4所述的化学机械平坦化设备，其特征在于所述晶圆卡盘为翻转结构，在其两面布置两套晶圆卡爪机构。
  8. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述清洗单元中装有机械手，将晶圆在抛光单元和清洗单元之间传输。
  9. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述装卸台可在抛光单元阵列的列方向上纵向移动，一个装卸台可对应一个以上的抛光单元。
  10. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述化学机械平坦化设备可以集成设备前端单元模块。
  11. 根据权利要求1所述的化学机械平坦化设备，其特征在于所述清洗单元包括兆声波清洗或滚刷刷洗以及晶圆干燥功能。
  12. 根据权利要求1所述的化学机械平坦化设备，其特征在于在所述抛光单元与装卸台之间设置可开启闭合的抛光门。
  13. 一种利用权利要求1所述的化学机械平坦化设备进行晶圆传输的方法，其特征在于，包含以下步骤：
    S1：在初始状态下，垂直运动机构(123)处于高位，使得晶圆卡盘(124)可以沿着水平方向自由行走；
    S2：当导向装置(121)运行到转载台或者装卸台(116)的上方时，垂直运动机构(123)下降到低位，晶圆卡盘(124)上安装的晶圆卡爪(125)抓取晶圆；
    S3：随后垂直运动机构(123)上升到高位，水平运动驱动装置(122)运行到下一个转载台(118)或者装卸台(116)的上方；
    S4：垂直运动机构(123)下降到低位，晶圆卡盘(124)上的晶圆卡爪(125)进行释放晶圆操作；
    S5：重复以上步骤，使得晶圆可以在转载台(118)和各个装卸台(116)之间实现传递。
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