CN111633520B

CN111633520B - Highly integrated thinning equipment

Info

Publication number: CN111633520B
Application number: CN202010524989.1A
Authority: CN
Inventors: 赵德文; 刘远航; 路新春; 李长坤; 吴云龙
Original assignee: Tsinghua University; Huahaiqingke Co Ltd
Current assignee: Tsinghua University; Huahaiqingke Co Ltd
Priority date: 2020-06-10
Filing date: 2020-06-10
Publication date: 2021-06-18
Anticipated expiration: 2040-06-10
Also published as: CN111633520A

Abstract

The utility model relates to a high integrated attenuate equipment includes: the equipment front-end module is arranged at the front end of the thinning equipment; the grinding module is arranged at the tail end of the thinning equipment; the polishing module is arranged between the equipment front-end module and the grinding module; the polishing module comprises a post-processing unit for post-processing the chemically and mechanically polished substrate, and the post-processing unit comprises a horizontal brushing device and a single-cavity cleaning device which are adjacently arranged in the width direction of the thinning equipment. The method combines grinding, chemical mechanical polishing and cleaning and drying processes, provides the most economic and effective technical route for processing the substrate, has compact structure and high integration level, can provide technical support for the stacking process of the ultra-high-density semiconductor, and is an important component for the high-density packaging development of the semiconductor and the like.

Description

Highly integrated thinning equipment

Technical Field

The utility model relates to a semiconductor substrate processing technology field especially relates to a highly integrated attenuate equipment.

Background

In a later process stage of manufacturing an Integrated Circuit/semiconductor (IC), in order to reduce a package mounting height, reduce a chip package volume, improve a thermal diffusion efficiency, an electrical property and a mechanical property of a chip, and reduce a processing amount of the chip, a back surface of a substrate needs to be thinned before subsequent packaging, and the thickness of the chip after the back surface is thinned may even reach less than 5% of an initial thickness.

With the rapid development of IC manufacturing technology, substrates tend to have larger diameters in order to increase IC chip yields and reduce unit manufacturing costs. The existing equipment is mostly used for processing small-sized substrates, and the requirement for processing large-diameter substrates cannot be met. As the diameter of the substrate increases, the size of equipment for processing the substrate increases, and the equipment often exceeds the available floor area and is difficult to transport and install.

Meanwhile, with the improvement of IC performance, higher requirements are put on the quality of the substrate, and the surface accuracy, surface integrity, surface roughness, surface damage degree, and the like of the substrate are required to meet very high standards. However, the increase in the size of the substrate causes a series of problems such as easy warpage and deformation of the substrate, difficulty in ensuring the surface accuracy and surface roughness, and low processing efficiency, and the conventional processing technology and equipment cannot meet the requirements. In addition, the manufacturing cost of the substrate processing factory building is high, high requirements are placed on the space occupancy rate, and the overlarge size of the equipment can cause space waste, so that the production cost is increased.

In summary, the thinning process for large-sized substrates in the prior art has the problems of poor processing effect, low surface quality and high production cost.

Disclosure of Invention

The present disclosure provides a highly integrated thinning apparatus, which aims to at least solve one of the technical problems existing in the prior art.

The utility model provides a high integrated attenuate equipment, it includes:

the equipment front-end module is used for realizing the in-and-out of the substrate and is arranged at the front end of the thinning equipment;

the grinding module is used for carrying out rough grinding and fine grinding on the substrate and is arranged at the tail end of the thinning equipment;

the polishing module is used for carrying out chemical mechanical polishing on the substrate by utilizing a bearing head capable of adjusting loading pressure in a partition mode according to the thickness distribution of the substrate after grinding is finished, and the polishing module is arranged between the equipment front-end module and the grinding module;

the polishing module comprises a post-processing unit for performing post-processing on the chemically and mechanically polished substrate, wherein the post-processing unit comprises a horizontal brushing device and a single-cavity cleaning device which are adjacently arranged in the width direction of the thinning equipment, and the horizontal brushing device and the single-cavity cleaning device have a common side wall.

In one embodiment, the apparatus front end module includes a substrate storage unit at a front end of the apparatus and a first transfer unit for taking out a substrate; the polishing module also comprises a second transmission unit, a third transmission unit and a chemical mechanical polishing unit;

the opposite two sides of the horizontal brushing device are respectively adjacent to the second transmission unit and the single-cavity cleaning device along the width direction of the thinning equipment, the other side of the horizontal brushing device is adjacent to the third transmission unit along the length direction of the thinning equipment, and the other side of the horizontal brushing device is adjacent to the first transmission unit;

the single-cavity cleaning device is adjacent to the chemical mechanical polishing unit in the length direction of the thinning equipment.

In one embodiment, the second transmission unit is positioned on one side of the long edge of the thinning equipment and is respectively adjacent to the equipment front end module and the grinding module;

the third transmission unit is respectively adjacent to the second transmission unit, the horizontal brushing device, the single-cavity cleaning device and the chemical mechanical polishing unit.

In one embodiment, the side wall of the horizontal brushing device opposite to the third transmission unit is provided with an opening and closing window for substrate to enter and exit;

in one embodiment, an opening and closing window for substrate entering is arranged on a vertical wall, forming an acute angle with the length direction of the thinning equipment, of the single-cavity cleaning device relative to the third transmission unit, and an opening and closing window for substrate taking out is arranged on a vertical wall, opposite to the first transmission unit, of the single-cavity cleaning device.

In one embodiment, the horizontal scrubbing apparatus comprises:

a substrate fixing assembly for horizontally supporting and fixing the substrate;

the first horizontal cleaning brush can rotate around a central axis in the horizontal direction and is used for horizontally cleaning the front surface of the substrate;

the second horizontal cleaning brush can rotate around the central axis in the horizontal direction and is used for horizontally cleaning the back of the substrate; and the number of the first and second groups,

and a cleaning tank for accommodating the substrate fixing assembly, the first horizontal cleaning brush, and the second horizontal cleaning brush and immersing the substrate in the cleaning solution.

In one embodiment, the substrate fixing assembly includes a fixing base and a plurality of supporting rollers disposed on the fixing base, wherein the supporting rollers cooperate to horizontally support the edge of the substrate and drive the substrate to horizontally rotate along the circumferential direction.

In one embodiment, the first transmission unit is respectively adjacent to the second transmission unit, the horizontal brushing device and the single-cavity cleaning device along the length direction of the thinning equipment, and the second transmission unit, the horizontal brushing device and the single-cavity cleaning device are arranged in parallel along the length direction of the thinning equipment.

In one embodiment, the second transfer unit includes a movable buffer portion capable of bidirectional movement, the movable buffer portion being capable of transporting the substrate from a first position proximate to the equipment front end module to a second position proximate to the grinding module and back from the second position to the first position;

the mobile buffer part and the chemical mechanical polishing unit are arranged in parallel along the length direction of the thinning equipment.

The highly integrated thinning equipment provided by the embodiment of the invention combines grinding, chemical mechanical polishing and cleaning and drying processes, has multiple substrate processing functions, has compact structure of each functional module, high equipment integration level and small occupied area, can realize ultra-precise flattening processing of the substrate, can provide technical support for a semiconductor stacking process with ultrahigh density, and is an important component for the development of high-density packaging of semiconductors.

Drawings

The advantages of the present disclosure will become clearer and more readily appreciated from the detailed description given in conjunction with the following drawings, which are given by way of illustration only, and which do not limit the scope of protection of the present disclosure, wherein:

fig. 1 to 2 show a thinning apparatus according to a preferred embodiment of the present disclosure in a schematic top view and a perspective view, respectively;

fig. 3 schematically shows a flow of operation of the thinning apparatus shown in fig. 1 to 2;

figures 4 to 5 show a grinding module of the thinning apparatus in schematic perspective and top views respectively;

figure 6 shows, in a schematic perspective view, a first transfer unit for the thinning apparatus, comprising a dry robot;

fig. 7 shows, in a schematic perspective view, a third transfer unit for the thinning apparatus, comprising a dry robot and a wet robot;

fig. 8 shows in a schematic perspective view a chemical-mechanical polishing unit of the thinning apparatus;

FIG. 9 illustrates, in schematic cross-sectional view, a carrier head of a chemical mechanical polishing unit;

fig. 10 shows a single-chamber cleaning device for a thinning apparatus in a schematic perspective view.

Detailed Description

The technical solution of the present invention will be described in detail with reference to the following embodiments and accompanying drawings. The embodiments described herein are specific embodiments of the present invention for the purpose of illustrating the concepts of the invention; the description is intended to be illustrative and exemplary and should not be taken to limit the scope of the invention. In addition to the embodiments described herein, those skilled in the art will be able to employ other technical solutions which are obvious based on the disclosure of the claims and the specification thereof, and these technical solutions include technical solutions which make any obvious replacement or modification of the embodiments described herein. It should be understood that, unless otherwise specified, the following description of the embodiments of the present invention is made for the convenience of understanding, and the description is made in a natural state where relevant devices, apparatuses, components, etc. are originally at rest and no external control signals and driving forces are given.

The substrate thinning technology provided by the embodiment of the disclosure is mainly applied to thinning the back surface of the substrate, where the back surface refers to a surface of the substrate where no device is laid, and is generally a substrate, and the substrate material may be silicon, silicon oxide, silicon nitride, silicon carbide, sapphire, or the like.

Fig. 1 and 2 show a thinning apparatus of one embodiment of the present disclosure in schematic top and perspective views, respectively. The thinning apparatus includes an apparatus front end module 1, a grinding module 3 for performing rough grinding and finish grinding on a substrate, and a polishing module 2 for performing chemical mechanical polishing and substrate transfer on the substrate after the rough grinding and finish grinding are completed.

The equipment front end module 1 is arranged on one side of the front end of the thinning equipment, is a transition module for conveying the substrate from the outside to the inside of the equipment machine table, and is used for realizing the entrance and exit of the substrate so as to realize the dry entrance and dry exit of the substrate. The grinding module 3 is disposed at the end of the thinning apparatus for grinding the substrate, such as performing rough grinding and finish grinding, or performing rough grinding, or performing finish grinding. The polishing module 2 is arranged between the equipment front-end module 1 and the grinding module 3, is used for carrying out chemical mechanical polishing on the substrate by utilizing the bearing head capable of adjusting pressure according to the thickness distribution and subarea of the substrate after the substrate is ground, and also has the function of transmitting the substrate among the three modules. The apparatus front end module 1 includes a substrate storage unit 11 and a first transfer unit 12. The polishing module 2 includes a second transfer unit 21, a third transfer unit 22, a chemical mechanical polishing unit 23, and a post-processing unit 24 (which will be described in further detail below). The grinding module 3 includes a grinding unit 31, a fourth transfer unit 32, a measurement unit 33, and a cleaning unit 34.

Fig. 3 shows, with arrows, the operating flow of the thinning apparatus shown in fig. 1 to 2, including:

the pick-and-place robot 121 of the first transfer unit 12 picks up the substrate from the substrate transport cassette 111 of the substrate storage unit 11;

a fixed buffer 211 for transferring the substrate to the second transfer unit 21 by the pick-and-place robot 121;

the dry robot 221 of the third transfer unit 22 transfers the substrate placed in the fixed buffer 211 to the moving buffer 212, and at this time, the moving buffer 212 approaches the fixed buffer 211;

the moving buffer 212 moves to be close to the grinding module 3 (as shown by a dotted line in fig. 3) with the substrate;

the simple robot of the fourth transfer unit 32 transports the substrate placed in the moving buffer 212 to the table 311 of the grinding unit 31, and fixes the substrate on the suction cup 312 corresponding to the current loading/unloading station;

the table 311 is rotated forward by 120 °, and the substrate is moved to the rough grinding station for rough grinding.

After the rough grinding is completed, the table 311 rotates forward by 120 °, and the substrate is moved to the finish grinding station for finish grinding.

After finish grinding, the table 311 rotates in the reverse direction by 240 °, and the substrate moves to a loading and unloading station;

the ground substrate is cleaned and dried by the cleaning unit 34 at the loading and unloading station, and then taken down by the simple manipulator and placed in the mobile buffer part 212;

the movement buffer unit 212 moves to the other end so that the wet robot 222 of the third transfer unit takes down the substrate and places the substrate in the storage unit 231 of the chemical mechanical polishing unit 23;

the substrate is polished in the chemical mechanical polishing unit 23; and carrying out chemical mechanical polishing on the substrate by utilizing the bearing head capable of adjusting the loading pressure according to the thickness distribution and the subarea of the substrate.

After the chemical mechanical polishing is completed, the substrate is taken out of the sheet storage part 231 of the chemical mechanical polishing unit 23 by the wet robot 222 of the third transfer unit 22 and then is carried into the horizontal brushing device 242, and the horizontal brushing device 242 brushes the substrate horizontally by a rolling brush;

after the horizontal brushing, the wet robot 222 transfers the substrate from the horizontal brushing apparatus 242 to the single-chamber cleaning apparatus 241, and cleans and dries the substrate;

after the substrate is cleaned and dried, the pick-and-place robot 121 of the first transfer unit 12 takes out the cleaned substrate from the post-processing unit 24 and stores the cleaned substrate in the substrate transfer cassette 111.

It will be appreciated that, during the grinding process, depending on the mounting positions of the rough grinding section and the finish grinding section, the table may be moved in a direction of rotation that is completely opposite to the above-described process, in other words, the layout shown in fig. 3 may be adopted such that the table is rotated in the forward direction in the clockwise direction while being rotated in the reverse direction in the counterclockwise direction, or the positions of the rough grinding section and the finish grinding section may be reversed such that the table is rotated in the forward direction in the counterclockwise direction while being rotated in the reverse direction in the clockwise direction. In addition, three substrates can be loaded on the three suckers simultaneously, and each sucker enables the substrate to execute different treatments according to different stations, so that the three working stations work simultaneously, the substrate treatment efficiency is improved, and the equipment utilization rate is improved.

The substrate is sequentially subjected to rough grinding, fine grinding and chemical mechanical polishing treatment, and the method specifically comprises the following steps:

step S1, performing rough grinding on the substrate, for example, using a rough grinding wheel to perform rough grinding on the substrate;

step S2, when the rough grinding is completed, performing a finish grinding on the substrate, for example, performing a finish grinding on the substrate by using a finish grinding wheel; the method comprises the following steps of finishing rough grinding when a first preset condition is reached, wherein the first preset condition is that the thickness of a substrate is measured to be reduced to a first preset value, the first preset value is within 150 micrometers, the thickness of the substrate before grinding is 775 micrometers, so that the reduction amount of hundreds of micrometers is required in the rough grinding process, materials are quickly removed by rough grinding, and the processing efficiency is improved;

and step S3, after finishing the fine grinding, using a carrier head capable of adjusting pressure according to the thickness distribution of the substrate. Wherein the finish grinding is completed when a second preset condition is reached, the second preset condition is that the thickness of the substrate is measured to be reduced to a second preset value, and the second preset value is between 10 and 50 mu m.

The rough grinding process includes: measuring the thickness of the substrate on line during rough grinding; and stopping feeding of the rough grinding tool when the thickness of the substrate reaches a first preset range, so that the rough grinding tool performs light grinding on the substrate for a first preset time.

The fine grinding process comprises the following steps:

1) enabling the fine grinding tool to perform fine grinding according to the initial feeding speed;

2) suspending the finish grinding when the thickness of the substrate reaches an intermediate target value, measuring a finish grinding thickness profile of the substrate, and adjusting a tilt angle of the finish grinding-related member according to the finish grinding thickness profile, wherein the adjusting the tilt angle of the finish grinding-related member includes: at least one of adjusting an inclination angle of a finish-grinding tool, adjusting an inclination angle of a holder for holding a substrate, and adjusting an axial positional relationship between the finish-grinding tool and the holder;

3) enabling the fine grinding tool to perform fine grinding at a second feeding speed; and

4) and stopping feeding of the fine grinding tool when the thickness of the substrate reaches a second preset range, so that the fine grinding tool performs light grinding on the substrate for a second preset time. .

When the substrate is ground, the surface to be thinned of the substrate is upwards placed to contact with a grinding tool positioned above the substrate, when the substrate is subjected to chemical mechanical polishing (S3), the surface to be thinned of the substrate is downwards placed to contact with a polishing pad positioned below the substrate, wherein after the substrate is ground and before the substrate is subjected to chemical mechanical polishing, the substrate is subjected to overturning treatment. The surface to be thinned is a back surface of the substrate, and the back surface is an opposite side of a device surface on which the electronic circuit is formed.

The chemical mechanical polishing process comprises:

1) obtaining the thickness distribution of the substrate before polishing; measuring a thickness profile of the finish-ground substrate before chemical mechanical polishing of the substrate, wherein the substrate thickness can be obtained using, for example, a noncontact optical measuring instrument; adjusting the loading pressure of the bearing head to each subarea on the surface of the substrate according to the thickness distribution;

2) pressing the substrate on the polishing pad by using the bearing head to carry out chemical mechanical polishing; during the chemical mechanical polishing of the substrate, measuring the thickness distribution of the substrate on line, and adjusting the loading pressure of the bearing head to each subarea of the substrate according to the thickness distribution of the substrate measured on line; preferably, the thickness mean value corresponding to each partition on the surface of the substrate is calculated based on the thickness distribution; comparing the thickness average value of each partition, and enabling the bearing head to apply corresponding loading pressure on the corresponding partition according to the thickness average value; wherein the loading pressure is positively correlated with the thickness mean of the corresponding partition;

3) it is judged whether or not the polishing stop condition is reached. If the polishing stopping condition is reached, finishing the chemical mechanical polishing; if the stop condition is not met, the process returns to step 34 to continue the chemical mechanical polishing.

In this embodiment, after rough grinding of the substrate, the substrate is subjected to finish grinding, and the finish-ground substrate is subjected to chemical mechanical polishing. The ultra-precision grinding realizes rapid material removal, and has the advantages of large material removal amount, low cost and high efficiency. The chemical mechanical polishing can improve the surface quality of the substrate and realize an ultra-flat and ultra-smooth surface. The method comprehensively considers multiple factors such as processing efficiency, processing cost, surface quality, pollution degree and the like, and the mode of combining the ultra-precision grinding and the chemical mechanical polishing process is the most economic and effective technical route.

In this embodiment, the total thickness deviation of the substrate is improved by the chemical mechanical polishing process. After the chemical mechanical polishing, the total thickness deviation of the substrate is reduced to be within 1 μm, the thickness of the substrate is reduced by 3 to 5 μm in the chemical mechanical polishing process, and the thickness of the substrate is reduced to be 7 to 10 μm after the polishing.

The substrate is placed upwards to be thinned in the coarse grinding process and the fine grinding process so as to contact the grinding wheel positioned above the substrate, and the coarse grinding process and the fine grinding process use the grinding wheel positioned above the substrate to rotate relative to the surface of the substrate so as to remove surface materials, so that the surface to be thinned of the substrate is placed upwards for grinding.

The base plate is in among the chemical mechanical polishing process do treat that the attenuate face is placed downwards with the polishing pad of contact position in base plate below, and chemical mechanical polishing process utilizes the carrier head to press the base plate on the polishing pad motion makes the base plate surface with the polishing pad contact removed gradually, so the face of treating the attenuate of base plate should place downwards and polish.

In this embodiment, since the substrate is subjected to rough grinding, finish grinding and chemical mechanical polishing on the same surface, that is, the surface to be thinned is a silicon substrate surface, the surface to be thinned of the substrate faces upward during grinding, and the surface to be thinned of the substrate faces downward during chemical mechanical polishing, the substrate needs to be turned over after the grinding process is completed, and the substrate can be turned over by using the third transmission unit.

The specific composition structure and function of each module are described below.

Device front-end module 1:

as shown in fig. 1 and 2, the apparatus front end module 1 includes a substrate storage unit 11 and a first transfer unit 12. The substrate storage unit 11 is disposed at a front end side of the thinning apparatus, and the first transfer unit 12 is disposed between the substrate storage unit 11 and the polishing module 2, for effecting transfer of the substrate between the substrate storage unit 11 and the polishing module 2.

The substrate storage unit 11 is composed of a plurality of Front Opening Unified Pod (FOUP) 111, and specifically may be two, three, or the like. The front-opening substrate transport box 111 is a container used for protecting, transporting and storing substrates in a semiconductor process, and its main components are a front-opening container capable of accommodating substrates and a front-opening door structure hermetically connected to an outer wall of the thinning apparatus so as to communicate the front-opening container with the inside of the apparatus.

As shown in fig. 6, the first transfer unit 12 includes a pick-and-place robot 121 and a first transfer rail 122, a base 123 of the pick-and-place robot 121 is disposed on the first transfer rail 122, the base 123 is slidable on the first transfer rail 122 to move between different positions, and a robot arm of the pick-and-place robot 121 is rotatable on the base 123 and is extendable or collapsible. The chip taking and placing manipulator is a drying manipulator and is used for taking and placing dry and clean substrates. The pick-and-place robot may pick up a substrate to be processed from the substrate storage unit 11 through the door structure of the substrate transport box 111 and send the substrate to the polishing module 2, and may also receive the processed substrate from the polishing module 2 and place the substrate in the substrate transport box 111.

Grinding module 3:

as shown in fig. 1 and 2, the grinding module 3 includes a grinding unit 31, a fourth transfer unit 32, a measuring unit 33, and a cleaning unit 34.

Fig. 4 and 5 show the grinding unit 31 in a schematic perspective view and a plan view, respectively. The illustrated grinding unit 31 includes a table 311, a rough grinding section 313, a finish grinding section 315, and a grinding liquid supply section. The table 311 is provided with a suction cup 312 for sucking the substrate, the rough grinding portion 313 is provided with a rough grinding wheel 314 for rough grinding the substrate, and the finish grinding portion 315 is provided with a finish grinding wheel 316 for finish grinding the substrate. The grinding process is to press a grinding wheel against the surface of the substrate and rotate the grinding wheel to grind off a certain thickness.

The workbench 311 can rotate around a vertical central axis thereof, three suckers which can rotate independently are uniformly distributed on the workbench and are respectively a first sucker, a second sucker and a third sucker, the three suckers are porous ceramic suckers with completely identical structures so as to realize vacuum adsorption of a substrate, and the centers of the three suckers and a connecting line of the center of the workbench 311 mutually form an included angle of 120 degrees. The three suction cups correspond to three stations 312, a rough grinding station, a finish grinding station, and a loading and unloading station, wherein two stations opposite to the grinding wheel are used for rough grinding and finish grinding, respectively, and one station is left for loading and unloading and cleaning of the substrate. The three suckers can be driven to switch among the three stations through the rotation of the workbench, so that the suckers can carry the substrate to circularly move according to the sequence of the loading and unloading station, the rough grinding station, the fine grinding station and the loading and unloading station. The present embodiment achieves full-automatic loading and unloading and continuous grinding and cleaning of the substrate by repeated cycles. The rotary worktable type substrate grinding has the advantages of high material removal rate, small substrate surface damage and easy realization of automation.

The rough grinding part 313 comprises a rough grinding wheel 314 in a cup-shaped structure, a rough grinding main shaft seat and a rough grinding feeding mechanism, the rough grinding wheel is connected to the bottom of the rough grinding main shaft to enable the rough grinding main shaft to drive the rough grinding wheel to rotate, so that the rough grinding wheel can rotatably grind the surface of a substrate, the rough grinding main shaft is connected with the rough grinding feeding mechanism through the rough grinding main shaft seat to move up and down, and the rough grinding wheel is controlled by the rough grinding feeding mechanism to carry out axial plunge feeding grinding relative to the substrate. In this embodiment, the rough grinding wheel may be a diamond grinding wheel, the surface of which is rough to realize rapid substrate grinding, reducing the substrate thinning time. During rough grinding, the feeding speed of the rough grinding wheel relative to the substrate is 2-10 μm/s so as to realize high-speed feeding, and the rotating speed of the rough grinding wheel is 2000-4000 rpm. The radius of the rough grinding wheel is matched with the radius of the substrate, and can be 1 to 1.2 times of the radius of the substrate. The thickness of the substrate is reduced by more than 600 μm in the rough grinding process, and after the rough grinding, the thickness of the substrate can be reduced to be within 150 μm.

The finish grinding portion 315 includes a finish grinding wheel 316 in a cup-shaped structure, a finish grinding spindle base and a finish grinding feed mechanism, the finish grinding wheel is connected to the bottom of the finish grinding spindle so that the finish grinding spindle drives the finish grinding wheel to rotate, thereby realizing the rotary grinding of the finish grinding wheel to the surface of the substrate, the finish grinding spindle is connected with the finish grinding feed mechanism through the finish grinding spindle base to move up and down, and the finish grinding wheel is controlled by the finish grinding feed mechanism to perform axial plunge feed grinding relative to the substrate. In this embodiment, the finish grinding wheel may be a diamond grinding wheel having a surface roughness lower than that of the rough grinding wheel, and since severe surface defects and losses may be generated by rapidly removing the surface material of the substrate by the rough grinding, the fine surface of the finish grinding wheel is used for low-speed grinding to reduce the thickness of the damaged layer on the surface of the substrate and improve the surface quality of the substrate. In the finish grinding, the feed speed of the finish grinding wheel relative to the substrate is 0.1-1 μm/s so as to realize low-speed feed to improve the grinding precision, and the rotating speed of the finish grinding wheel is 2000-4000 rpm. The radius of the finish grinding wheel matches the radius of the substrate and may be 1 to 1.2 times the radius of the substrate. The thickness of the substrate is reduced by the finish grinding process to be 50 to 100 μm, and after the finish grinding, the thickness of the substrate may be reduced to be 10 to 50 μm.

The grinding fluid supply part is used for spraying grinding fluid to the surface of the substrate to assist grinding during rough grinding and/or fine grinding, and the grinding fluid can be deionized water.

The fourth transfer unit 32 includes a simple robot 321, the simple robot 321 takes the substrate from the moving buffer 212 and feeds the substrate into the grinding unit 31 for grinding, and after the grinding and cleaning are completed, the simple robot 321 takes the substrate from the grinding unit 31 and places the substrate in the moving buffer 212 for subsequent transfer of the substrate. The simple robot 321 is provided therein with a vacuum line to vacuum-adsorb the substrate.

The measurement unit 33 includes a contact-type measuring instrument 331 and a non-contact-type optical measuring instrument 332, and can realize online monitoring of the substrate thickness. The probe of the contact type measuring instrument is pressed on the surface of the substrate to measure the thickness of the substrate by using the height difference of the upper surface and the lower surface of the substrate. The contact measuring apparatus is provided with two sets, which are respectively arranged in the rough grinding part 313 and the fine grinding part 315. The non-contact optical measuring instrument irradiates the substrate with infrared light and calculates the thickness of the substrate according to different reflected lights of the upper surface and the lower surface of the substrate.

The cleaning unit 34 includes a first cleaning part 341 and a second cleaning part 342. The first cleaning portion 341 is used for cleaning and polishing the suction cup, and has a rotatable first body, the bottom of the first body is provided with a suction cup cleaning brush and a suction cup polishing oilstone, and the bottom of the first body is also provided with a through hole for spraying cleaning fluid to the suction cup through a pipeline inside the first body. The second cleaning part 342 is used for cleaning the substrate, and has a rotatable second body, a brush for cleaning the substrate is provided at the bottom of the second body, and a through hole is further provided at the bottom of the second body to spray cleaning liquid to the substrate through a pipe inside the second body.

And (3) polishing module 2:

as shown in fig. 1 and 2, the polishing module 2 includes a second transfer unit 21, a third transfer unit 22, a chemical mechanical polishing unit 23, and a post-processing unit 24. The chemical mechanical polishing unit 23 and the second transfer unit 21 are arranged in parallel along the length direction of the apparatus. The post-treatment unit 24 is located between the first transfer unit 12 and the chemical mechanical polishing unit 23. The third transfer unit 22 is adjacent to each of the first transfer unit 12, the second transfer unit 21, the chemical mechanical polishing unit 23, and the post-processing unit 24, and serves to transfer the substrates to and from each other among the first transfer unit 12, the second transfer unit 21, the chemical mechanical polishing unit 23, and the post-processing unit 24.

The second transfer unit 21 includes a fixed buffer 211 and a moving buffer 212 for temporarily storing the substrate and shipping the substrate. The fixed buffer 211 is provided at a position adjacent to the front end module 1 to temporarily store the substrate transferred from the front end module 1 or the substrate to be transferred to the front end module 1. The movement buffer 212 is provided along the direction from the equipment front end module 1 to the grinding module 3 to form a substrate transfer path between the equipment front end module 1 and the grinding module 3, and substrates are transferred between the equipment front end module 1, the polishing module 2, and the grinding module 3 through the movement buffer 212. The movement buffer unit 212 includes a fixing mechanism, a centering mechanism, and a horizontal movement mechanism, the centering mechanism is provided on the fixing mechanism to position the substrate placed on the fixing mechanism to a position concentric with the fixing mechanism, and the fixing mechanism is connected to the horizontal movement mechanism to horizontally move the fixing mechanism with the substrate loaded thereon. The movable buffer portion 212 is movable in both directions in the horizontal direction, and the movable buffer portion 212 is movable in a forward or reverse direction between a first position close to the fixed buffer portion 211 or the front end module 1 of the apparatus and a second position close to the grinding module 3 to transfer the substrate to the grinding module 3 or receive the substrate transferred from the grinding module 3 and transfer the substrate to another unit. The substrate is taken out from the front end module 1 and then transported to the grinding module 3 via the mobile buffer 212 for grinding; after the substrate is ground in the grinding module 3, the substrate is transported to the chemical mechanical polishing unit 23 in the polishing module 2 via the movement buffer 212 to be polished.

As exemplarily shown in fig. 1 and 2, the moving buffer 212 has only one substrate transfer path, and can only transport the substrate from the first position to the second position or transport the substrate from the second position to the first position. Of course, it is also contemplated that the moving buffer 212 may include a plurality of substrate transfer lanes, thereby enabling simultaneous transport of one substrate from a first location to a second location and transport of another substrate from the second location to the first location. For example, the moving buffer part 212 may include a plurality of moving buffers that are movable bidirectionally, and the plurality of moving buffers may be arranged side by side in a lateral direction or arranged up and down in a vertical direction.

As shown in fig. 7, the third transfer unit 22 includes a dry robot 221 and a wet robot 222. The dry robot 221 may transfer the substrate from the fixed buffer part 211 of the second transfer unit 21 to the moving buffer part 212, and the wet robot 222 may transfer the ground substrate from the moving buffer part 212 to the chemical mechanical polishing unit 23, or transfer the chemical mechanical polished substrate from the chemical mechanical polishing unit 23 to the post-processing unit 24. As in the embodiment shown in fig. 1 and 2, the moving buffer 212 carries both the dry substrate to be ground conveyed from the front end module 1 and the wet substrate after grinding, so that the dry robot 221 is spaced apart from the moving buffer 212 in the vertical direction during the movement of the dry robot 221 above the moving buffer 212, i.e., spaced apart from the moving buffer 212 in the vertical direction, in order to prevent the dry robot 221 from being contaminated by the wet moving buffer, so that the dry robot 221 does not directly contact the moving buffer 212 during the conveyance of the substrate onto the moving buffer 212. In this way, contamination of the dry robot 221 due to the transfer of wet substrates by the moving buffer 212 is avoided. The dry robot 221 and the wet robot 222 are fixed to the same base and can rotate around the base, which can move horizontally.

It will be appreciated that the composition of the third transfer unit 22 is only schematically illustrated in fig. 1 and 2, and in practical applications, the dry robot 221 and the wet robot 222 are at different heights to prevent interference during movement. The dry robot 221 and the wet robot 222 can perform a moving operation between a long distance and a short distance, and the robot arms of the both can be extended to extend an operation distance and can be folded to retract the operation distance.

As shown in fig. 8, Chemical Mechanical Planarization (CMP) is a global surface Planarization technique that can precisely and uniformly planarize a substrate to a desired thickness and flatness. The chemical mechanical polishing unit 23 receives the substrate from the third transfer unit 22 and performs a chemical mechanical polishing process to improve the planarization effect of the substrate. As shown in fig. 1 and 2 and in fig. 8, the chemical mechanical polishing unit 23 includes a storage plate portion 231, a polishing disk 232, a polishing pad 233 adhered to the polishing disk 232, a carrier head 234 that adsorbs and rotates the substrate, a dresser 235 that dresses the polishing pad 232, and a liquid supply portion 236 that supplies polishing liquid to the surface of the polishing pad 233. Before polishing starts, the wet robot 222 of the third transfer unit 22 carries the substrate to the storage section 231, and the carrier head 234 moves from the storage section 231 to above the polishing platen 232 in the radial direction of the polishing platen 232 after loading the substrate thereon. During chemical mechanical polishing, the carrier head 234 presses the substrate against the polishing pad 233 covered by the surface of the polishing pad, and the size of the polishing pad 233 is larger than the size of the substrate to be polished, for example, 1.2 times or more the size of the substrate, thereby ensuring uniform polishing of the substrate. The carrier head 234 performs a rotating motion and reciprocates in a radial direction of the polishing platen 232 so that the surface of the substrate contacting the polishing pad 233 is gradually polished while the polishing platen 232 rotates, and the liquid supply part 236 sprays polishing liquid onto the surface of the polishing pad 233. The substrate is rubbed against the polishing pad 233 by the relative movement of the carrier head 234 and the polishing platen 232 under the chemical action of the polishing liquid to perform polishing. Polishing liquid consisting of submicron or nanometer abrasive particles and chemical solution flows between a substrate and a polishing pad 233, the polishing liquid is uniformly distributed under the action of transmission and rotating centrifugal force of the polishing pad 233 to form a layer of liquid film between the substrate and the polishing pad 233, chemical components in the liquid and the substrate generate chemical reaction to convert insoluble substances into easily soluble substances, then the chemical reactants are removed from the surface of the substrate through micro-mechanical friction of the abrasive particles and dissolved into the flowing liquid to be taken away, namely surface materials are removed in an alternate process of chemical film forming and mechanical film removing to realize surface planarization treatment, thereby achieving the purpose of global planarization. During polishing, the dresser 235 serves to dress and activate the topography of the polishing pad surface 233. The dresser 235 can remove foreign particles remaining on the surface of the polishing pad, such as abrasive particles in the polishing liquid and waste materials falling off from the surface of the substrate, and can also flatten the surface deformation of the polishing pad 233 caused by the grinding, thereby ensuring the consistency of the surface topography of the polishing pad 233 during the polishing and further stabilizing the polishing removal rate. After the polishing is completed, the carrier head 234 adsorbs the substrate to place it on the deposit section 231, and the third transfer unit 22 takes the substrate from the deposit section 231 and conveys the substrate to the post-processing unit 24.

Fig. 9 is a schematic structural diagram of a carrier head 234. The carrier head 234 includes an upper structure 2341 coupled to the carrier head drive shaft and a lower structure 2342 coupled by a flexible connection. The substructure 2342 includes a gimbal, a base 2343, a flexible membrane 2344, and a retaining ring 2345. The elastic membrane 2344 and the retaining ring 2345 are both fixed to the lower surface of the base 2343, and the annular retaining ring 2345 is located outside the elastic membrane 2344 and is disposed around the elastic membrane 2344. The elastic membrane 2344 is used to attract and apply a downward force to the substrate, and may be made of an elastic material, for example, chloroprene or silicone rubber. The retaining ring 2345 is used to hold the substrate under the elastic membrane 2344 to prevent the substrate from slipping out. As shown in fig. 9, the elastic membrane 2344 has a plurality of concentric pressure-adjustable chambers therein, and the example of fig. 9 having 5 pressure-adjustable chambers is described, which includes a first chamber Z1, a second chamber Z2, a third chamber Z3, a fourth chamber Z4 and a fifth chamber Z5, which are concentrically arranged from the center to the outside. The central first chamber Z1 is circular and the second to fifth chambers Z2 to Z5 are concentric rings. It is clear that the number of chambers shown in fig. 9 is only an example, and that other numbers, such as six, seven, etc., are possible. Particularly advantageously, the number of pressure-adjustable chambers is seven.

The bottom of the carrier head employed in this embodiment is provided with at least five pressure-adjustable chambers, preferably seven pressure-adjustable chambers, such that the pressure applied to each zone of the substrate surface can be adjusted by controlling the pressure in each pressure-adjustable chamber. The internal pressures of the 1 st chamber Z1 through the fifth chamber Z5 are independent of each other and can be varied, respectively, and accordingly, different chambers of the carrier head divide the surface of the substrate into a corresponding plurality of zones, thereby enabling independent adjustment of the polishing pressures of five concentric annular zones corresponding to the surface of the substrate. Each chamber can apply different pressures to the corresponding substrate surface subarea, and different pressures can be applied to different subareas of the substrate surface by respectively controlling the pressure of fluid such as pressurized air supplied to the chambers. The CMP multi-region pressure intelligent control technology realizes accurate compensation and regulation of the surface shape of the substrate, and effectively improves the overall thickness uniformity of the thinned substrate.

As shown in fig. 1 to 3, the post-treatment unit 24 includes a horizontal brushing device 242 and a single-chamber cleaning device 241 adjacently disposed in the width direction of the thinning apparatus to clean and dry the polished substrate. The horizontal brushing device 242 is used to horizontally brush the chemically mechanically polished substrate, and the single-chamber cleaning device 241 is used to horizontally rinse and spin-dry the substrate.

As shown in fig. 1 to 3, two opposite sides of the horizontal brushing device 242 are respectively adjacent to the second transmission unit 21 and the single-chamber cleaning device 241 along the width direction of the thinning apparatus, the other side of the horizontal brushing device 242 is adjacent to the third transmission unit 22 along the length direction of the thinning apparatus, and the other side of the horizontal brushing device 242 is adjacent to the first transmission unit 12. The side wall of the horizontal brush device 242 facing the third transfer unit 22 has an open/close window for substrate entrance and exit, wherein the single-chamber cleaning device 241 is integrally and adjacently disposed in connection with the horizontal brush device 242 as shown in fig. 2, and the single-chamber cleaning device 241 and the horizontal brush device 242 have a common side wall 24A, and the side wall 24A is configured as a detachable side wall for maintenance.

Further, as shown in fig. 2, the single chamber cleaning device 241 is not composed of four vertical side walls perpendicular to each other, and further includes a side wall 24B inclined with respect to the length and width directions of the thinning apparatus in a plan view, and the side wall 24B has one opening/closing window of two opening/closing windows of the single chamber cleaning device 241 for feeding the substrate into the single chamber cleaning device 241, so that the inclined side wall is advantageous for setting a robot by fully utilizing the space in the thinning apparatus and reducing the path for transferring the substrate to improve the production efficiency, and preferably, the side wall 24B forms an inclined angle of 45 degrees with the length direction of the thinning apparatus.

In one embodiment, horizontal brushing apparatus 242 comprises:

a substrate fixing assembly for horizontally supporting and fixing the substrate; the substrate fixing assembly comprises a fixing seat and a plurality of supporting rollers arranged on the fixing seat, and the supporting rollers are matched to horizontally support the edge of the substrate and drive the substrate to horizontally rotate along the circumferential direction;

The horizontal brushing device 242 horizontally supports the substrate by using the support rollers and drives the substrate to horizontally rotate along the circumferential direction, and meanwhile, the first horizontal cleaning brush and the second horizontal cleaning brush respectively attach to the surface of the substrate in the upper and lower directions to rotate, and the cleaning solution is matched to brush and remove the pollutants on the surface of the substrate.

As shown in fig. 1-3, the single chamber cleaning device 241 is a cleaning and drying integrated device. The single-cavity cleaning device 241 is arranged between the chemical mechanical polishing unit 23 and the equipment front-end module 1 so as to be conveniently and quickly conveyed to the equipment front-end module 1 for storage after the substrates are cleaned and dried, and the single-cavity cleaning device 241 is adjacent to the chemical mechanical polishing unit 23 along the length direction of the thinning equipment. A first opening and closing window for substrate entering is formed in a vertical wall, facing the third transmission unit 22, of the single-cavity cleaning device 241, and an included angle of the vertical wall and the length direction of the thinning equipment is an acute angle, so that the third transmission unit 22 can conveniently take and place the substrate to the single-cavity cleaning device 241, and a second opening and closing window for substrate taking out is formed in a vertical wall, facing the first transmission unit 12, of the single-cavity cleaning device 241, so that the first transmission unit 12 can conveniently take and place the substrate to the single-cavity cleaning device 241.

As shown in fig. 10, the single chamber cleaning device 241 includes a carrying portion 2411 for holding and rotating the substrate w, a fluid supply portion (not shown) for ejecting a fluid to the substrate, a shutter portion 2412 for blocking the splashed fluid, and a fluid collection chamber (not shown). The carrier portion 2411, fluid supply portion, and baffle portion 2412 are all disposed within a closed fluid collection chamber to prevent fluid leakage. The bearing portion 2411 keeps the substrate horizontal, and the bearing portion 2411 drives the substrate to rotate around its vertical central axis. The baffle portion 2412 is disposed around the bearing portion 2411, and the baffle portion 2412 may be formed of an annular baffle member. The fluid supply unit is used for spraying cleaning liquid or drying gas on the surface of the substrate, and under different actual requirements, the fluid supply unit can spray water, acid solution and/or alkaline solution, drying gas and the like on the substrate in sequence according to different operation sequences, and different liquid can be guided into different chambers by using different baffles.

During cleaning, the single-chamber cleaning device 241 horizontally supports the substrate by the supporting portion 2411 and drives the substrate to horizontally rotate along the circumferential direction, and the fluid supply portion sprays cleaning fluid to the surface of the substrate to wash the surface. During drying, the supporting portion 2411 drives the substrate to rotate at high speed to spin-dry the surface of the substrate.

In one embodiment, the baffle portion 2412 includes at least two concentrically spaced annular baffles and a baffle elevating unit for controlling the annular baffles to independently elevate. The annular baffles may be configured to be individually liftable and lowerable, and different liquids sputtered from the substrate may be guided to different positions when different baffles are opposed to the peripheral end surface of the substrate.

In one embodiment, the fluid supply includes at least one upper surface spray assembly and at least one lower surface spray assembly; the upper surface spraying assembly and the lower surface spraying assembly are spraying assemblies with the same structure, each spraying assembly comprises a nozzle, a mechanical arm and a flow supply pipeline, the flow supply pipeline is communicated with the nozzles, and the mechanical arm is connected with the nozzles to drive the nozzles to move. When the nozzle sprays fluid, the mechanical arm drives the nozzle to do reciprocating swing around the shaft, for example, the mechanical arm drives the nozzle to do reciprocating swing on two sides of the nozzle aligned with the circle center of the substrate during cleaning, and therefore the contact area of the fluid and the surface of the substrate is increased.

In one embodiment, the single chamber cleaning device 241 is disposed in a closed tank (not shown) having an air supply unit at the top and an air exhaust unit at the bottom. The air supply unit comprises a fan and a filter layer to convey clean air into the box body. The exhaust unit comprises a gas-liquid separation device and an air extractor, the gas-liquid separation device performs gas-liquid separation on the collected fluid, the separated liquid is discharged through a liquid discharge pipeline, and the gas is extracted by the air extractor and discharged through an exhaust pipeline. The side wall of the box body can be provided with an observation window so as to facilitate an operator to observe the operation condition of each part in the box.

The drawings in the present specification are schematic views to assist in explaining the concept of the present invention, and schematically show the shapes of respective portions and their mutual relationships. It should be understood that the drawings are not necessarily to scale, the same reference numerals being used to identify the same elements in the drawings in order to clearly show the structure of the elements of the embodiments of the invention.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A highly integrated thinning apparatus, comprising:

the polishing module comprises a post-processing unit for post-processing the chemically and mechanically polished substrate, wherein the post-processing unit comprises a horizontal brushing device and a single-cavity cleaning device which are adjacently arranged along the width direction of the thinning equipment, and the horizontal brushing device and the single-cavity cleaning device have a common side wall;

the equipment front end module comprises a substrate storage unit positioned at the front end of the equipment and a first transmission unit used for taking out the substrate;

the polishing module also comprises a second transmission unit, a third transmission unit and a chemical mechanical polishing unit;

2. The highly integrated thinning apparatus according to claim 1, wherein the second transmission unit is located on one side of a long side of the thinning apparatus and adjacent to the apparatus front end module and the grinding module, respectively;

3. The highly integrated thinning apparatus according to claim 1, wherein a side wall of the horizontal brushing device facing the third transfer unit has an opening and closing window for substrate entry and exit.

4. The highly integrated thinning equipment according to claim 1, wherein the single-cavity cleaning device faces the vertical wall of the third transmission unit, which forms an acute angle with the length direction of the thinning equipment, and is provided with a first opening and closing window for the substrate to enter, and the single-cavity cleaning device faces the vertical wall of the first transmission unit and is provided with a second opening and closing window for the substrate to be taken out.

5. The highly integrated thinning apparatus according to claim 1, wherein the horizontal brushing device comprises:

and the cleaning tank is used for accommodating the substrate fixing assembly, the first horizontal cleaning brush and the second horizontal cleaning brush and immersing the substrate in the cleaning solution.

6. The highly integrated thinning apparatus according to claim 5, wherein the substrate fixing assembly comprises a fixing base and a plurality of supporting rollers disposed on the fixing base, and the plurality of supporting rollers cooperate to horizontally support the edge of the substrate and drive the substrate to horizontally rotate along the circumferential direction.

7. The highly integrated thinning apparatus according to claim 1, wherein the first transmission unit is adjacent to the second transmission unit, the horizontal brushing device and the single-cavity cleaning device along the length direction of the thinning apparatus, and the second transmission unit, the horizontal brushing device and the single-cavity cleaning device are arranged in parallel along the length direction of the thinning apparatus.

8. The highly integrated thinning apparatus according to claim 1, wherein the second transfer unit includes a movable buffer portion capable of bidirectional movement, the movable buffer portion being capable of transporting the substrate from a first position near the apparatus front end module to a second position near the grinding module and back from the second position to the first position;