TWI856586B - Precision granite pneumatic hydrostatic motion platform device - Google Patents

Abstract

A precision granite pneumatic hydrostatic motion platform device includes a guide rail unit, a slide unit, a pneumatic hydrostatic bearing unit and a linear motor unit. The guide rail unit includes a base and a guide rail assembly, the slide unit includes a base, two slide blocks, two side slide blocks and an air guide channel assembly, the pneumatic hydrostatic bearing unit allows an air film to be generated between the slide unit and the guide rail unit, and the linear motor unit can drive the slide unit to generate linear movement relative to the guide rail unit along the long axis. By utilizing the hydrostatic buoyancy, the slide unit can slide non-contactly on the high-precision granite guide rail unit. When used with the linear motor unit, it can achieve high positioning accuracy and high acceleration and deceleration motion that is superior to metal rails, and can be applied to high-precision semiconductor processing equipment.

Description

Precision granite pneumatic hydrostatic motion platform device

The present invention relates to a precision mechanical device, in particular to a precision granite pneumatic hydrostatic motion platform device.

In today's semiconductor manufacturing process, in order to continue to break Moore's Law: "The number of transistors that can be accommodated per unit area of an integrated circuit will double approximately every two years", in addition to continuously improving the semiconductor photolithography process or changing the transistor device structure (such as fin field effect transistor FinFET), 3D stacking packaging technology has also been developed in chip packaging technology, that is, a 3DIC packaging design that stacks more silicon chips on a silicon chip. In the process, a precise positioning platform is required to carry the wafer for rapid movement to perform laser processing or wafer inspection at different locations, and it has also become an indispensable key component for semiconductor precision processing. However, problems such as heat and power loss generated during high-speed movement have gradually emerged. The linear slide rails (ball bearings) made of traditional metal materials (stainless steel or aluminum alloy) can no longer meet the precision and stability requirements of semiconductor manufacturing processes, and are no longer feasible in terms of processing costs, yield and service life.

Although the People's Republic of China's authorized announcement number CN202539944U discloses that by using a solid granite X-axis, X-axis slide, crossbeam and workbench, it can effectively absorb harmful vibration waves in the milling process, eliminate vibration marks on the workpiece surface, thereby improving the workpiece surface processing accuracy and tool durability. In addition, the US patent announcement number US7845257B2 discloses that the main structural part is formed by inorganic materials such as granite and alumina ceramics, so that the error caused by thermal displacement can be minimized, so that high-precision machining of nano-level workpieces can be performed.

However, the applicant believed that the precision machining technology still needed to be improved, and finally the present invention was born.

Therefore, the purpose of the present invention is to provide a precision granite pneumatic hydrostatic motion platform device that can improve processing accuracy.

Therefore, the precision granite pneumatic hydrostatic motion platform device of the present invention comprises a guide rail unit, a slide unit, a pneumatic hydrostatic bearing unit and a linear motor unit. The guide rail unit extends along a long axis and is made of granite material, and comprises a base and a guide rail assembly fixed to the base, the guide rail assembly having at least one top surface, two bottom surfaces opposite to the top surface, and two outer side surfaces intersecting the top surface and the bottom surface at an angle. The slide unit can slide on the guide rail unit along the long axis, and includes a pedestal relative to the top surface, two lower slide blocks respectively relative to the bottom surfaces, two side slide blocks respectively connected between the pedestal and the lower slide blocks, and an air guide channel group connecting the pedestal, the lower slide blocks and the side slide blocks. The side slide blocks are relative to the outer side surfaces. The pedestal has two side ends which are oppositely arranged along a transverse axis perpendicular to the long axis, and each side end and the corresponding side slide block and the lower slide block together form an inverted U-shaped side frame. The pneumatic pressure bearing unit is connected to the air guide channel assembly and includes a first pneumatic pressure bearing assembly fixed to the base and opposite to the top surface, a second pneumatic pressure bearing assembly fixed to the lower slide blocks and opposite to the bottom surfaces, and a third pneumatic pressure bearing assembly fixed to the side slide blocks and opposite to the outer side surfaces. The pneumatic pressure bearing unit allows an air film to be generated between the slide unit and the guide rail unit. The linear motor unit includes a stator mounted on the guide rail unit, and a mover mounted on the base of the slide unit and opposite to the stator. The linear motor unit can drive the slide unit to generate linear movement along the long axis relative to the guide rail unit.

The effect of the present invention is that the overall combination can reduce the stroke size requirements of ultra-precision processing equipment and fully exert the precision capability of the processing equipment. By utilizing the hydrostatic buoyancy, the slide unit can slide non-contactly on the high-precision granite guide rail unit. When combined with the linear motor unit, it can achieve high positioning accuracy and high acceleration and deceleration motion that is superior to metal rails, and can be applied to high-precision semiconductor processing equipment.

100: Hydrostatic motion platform device

10: Guide rail unit

11: Base

12: Guide rail assembly

120: Side seat

121: Top

122: Bottom

123: Outer side

124: Inner side

20: Sliding seat unit

21: Pedestal

211: Side end

212: Bottom end surface

213: First slot

22: Slide down block

221: Upper end surface

222: Second bezel

23: Side slider

231: Side surface

232: The third slot

24: Airway Group

241: First airway

242: Second airway

243: The third airway

25: Side frame

30: Hydrostatic bearing unit

31: The first hydrostatic bearing set

311: The first hydrostatic bearing

32: Second pneumatic hydrostatic bearing set

321: Second pneumatic hydrostatic bearing

33: The third hydrostatic bearing set

331: The third hydrostatic bearing

34: The fourth hydrostatic bearing set

40: Linear motor unit

41: Stator

42: Movers

51: Limit switch

52: Position sensor

X: Long axis

Y: horizontal axis

10’: Rail unit

11’: Base

12’: Rail assembly

120’: Side seat

13’: Recessed space

20’: Sliding seat unit

21’: Pedestal

26’: Extension block

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: FIG. 1 is a three-dimensional assembly diagram of a first embodiment of the precision granite gas hydrostatic motion platform device of the present invention; FIG. 2 is a top view of the first embodiment; FIG. 3 is a cross-sectional view along line III-III in FIG. 2; FIG. 4 is a partially enlarged schematic diagram of FIG. 3; FIG. 5 is a three-dimensional schematic diagram of the first embodiment in a stacked configuration; FIG. 6 is a cross-sectional schematic diagram of a second embodiment of the precision granite gas hydrostatic motion platform device of the present invention; FIG. 7 is a cross-sectional schematic diagram of a third embodiment of the precision granite gas hydrostatic motion platform device of the present invention; and FIG. 8 is a cross-sectional schematic diagram of a fourth embodiment of the precision granite gas hydrostatic motion platform device of the present invention.

Before the present invention is described in detail, it should be noted that similar components are represented by the same numbers in the following description.

Referring to Figures 1 to 4, a first embodiment of the precision granite pneumatic hydrostatic motion platform device 100 of the present invention includes a guide rail unit 10, a slide unit 20, a pneumatic hydrostatic bearing unit 30 and a linear motor unit 40.

The guide rail unit 10 extends along a long axis X and is made of granite, and includes a base 11 and a guide rail assembly 12 fixed to the base 11. The guide rail assembly 12 of this embodiment is a two-piece type, which is screwed to the base 11 respectively, and the guide rail assembly 12 has two side seats 120 arranged at intervals along a transverse axis Y perpendicular to the long axis X. Each side seat 120 has a top surface 121, a bottom surface 122 opposite to the top surface 121, an outer side surface 123 intersecting the top surface 121 and the bottom surface 122 at an angle, and an inner side surface 124 intersecting the top surface 121 at an angle and arranged opposite to the outer side surface 123.

The slide unit 20 can slide on the guide rail unit 10 along the long axis X, and includes a base 21 relative to the top surfaces 121, two lower slide blocks 22 respectively relative to the bottom surfaces 122, two side slide blocks 23 respectively connected between the base 21 and the lower slide blocks 22, and an air guide channel set 24 connecting the base 21, the lower slide blocks 22 and the side slide blocks 23. The base 21 has two side end portions 211 oppositely arranged along the transverse axis Y, a bottom end surface 212 relative to the top surfaces 121, and two first embedding grooves 213 respectively corresponding to the side end portions 211 and recessed by the bottom end surface 212. Each of the lower slide blocks 22 has an upper end surface 221 relative to the bottom surfaces 122, and a second embedding groove 222 recessed from the upper end surface 221. Each of the side slide blocks 23 has a side end surface 231 relative to the outer side surfaces 123, and a third embedding groove 232 recessed from the side end surface 231. Each side end portion 211 and the corresponding side slide block 23 and the lower slide block 22 together form an inverted U-shaped side frame 25. The air guide channel set 24 has a plurality of first air guide channels 241 disposed inside the base 21 and connected to the first embedded grooves 213, a plurality of second air guide channels 242 disposed inside the lower slide blocks 22 and connected to the second embedded grooves 222, and a plurality of third air guide channels 243 disposed inside the side slide blocks 23 and connected to the third embedded grooves 232. The first air guide channels 241, the second air guide channels 242 and the third air guide channels 243 are connected to each other.

The pneumatic pressure bearing unit 30 includes a first pneumatic pressure bearing set 31 fixed to the base 21 and opposite to the top surfaces 121, a second pneumatic pressure bearing set 32 fixed to the lower slide blocks 22 and opposite to the bottom surfaces 122, and a third pneumatic pressure bearing set 33 fixed to the side slide blocks 23 and opposite to the outer side surfaces 123. The pneumatic pressure bearing unit 30 allows an air film to be generated between the slide unit 20 and the guide rail unit 10. That is, the first pneumatic pressure bearing assembly 31 has a plurality of first pneumatic pressure bearings 311 respectively embedded in the first embedding grooves 213, and the first pneumatic pressure bearing assembly 31 allows air film to be generated between the pedestal 21 and the top surfaces 121. The second pneumatic pressure bearing assembly 32 has a plurality of second pneumatic pressure bearings 321 respectively embedded in the second embedding grooves 222, and the second pneumatic pressure bearing assembly 32 allows air film to be generated between the lower slide blocks 22 and the bottom surfaces 122. The third pneumatic bearing assembly 33 has a plurality of third pneumatic bearings 331 respectively embedded in the third embedding grooves 232. The third pneumatic bearing assembly 33 allows air film to be generated between the side sliders 23 and the outer side surfaces 123. The first pneumatic bearings 311, the second pneumatic bearings 321 and the third pneumatic bearings 331 are made of porous ceramic materials or other porous materials (e.g., materials containing porous graphite layers).

The linear motor unit 40 includes a stator 41 mounted on the guide rail unit 10, and a mover 42 mounted on the bottom end surface 212 of the slide unit 20 and opposite to the stator 41. The stator 41 is fixed to the base 11 and located between the side seats 120. The linear motor unit 40 can drive the slide unit 20 to generate linear movement along the long axis X relative to the guide rail unit 10.

In order to further understand the effects of the components of the present invention, the technical means used, and the expected effects, the following will be explained. I believe that this will provide a deeper and more specific understanding of the present invention.

As shown in Figures 1 to 3, when the overall assembly is completed, the slide unit 20 is sleeved on the outside of the guide rail unit 10, and the pneumatic hydrostatic bearing unit 30 is also pre-set on the slide unit 20, and the linear motor unit 40 is set between the guide rail unit 10 and the slide unit 20.

When the linear motor unit 40 is started, high-pressure air is also introduced into the air guide channel set 24 at the same time, and the pressure airflow is guided to the first pneumatic bearings 311 through the first air guide channels 241, the pressure airflow is guided to the second pneumatic bearings 321 through the second air guide channels 242, and the pressure airflow is guided to the third pneumatic bearings 331 through the third air guide channels 243, and an air film is generated between the base 21 and the top surfaces 121, between the lower slide blocks 22 and the bottom surfaces 122, and between the side slide blocks 23 and the outer side surfaces 123. An air flotation effect (similar to the function of a linear slide) is generated between the slide unit 20 and the guide rail unit 10, and the slide unit 20 is provided with smooth sliding relative to the guide rail unit 10, and the straightness of the slide unit 20 is maintained.

Therefore, the precision granite pneumatic hydrostatic motion platform device of the present invention uses the pneumatic hydrostatic bearing unit 30 (Air Bearing). Because the hydrostatic air bearing (air flotation) is used for linear guidance, the friction of the sliding surface is extremely small, and there will be no sticking phenomenon. Therefore, the operation process is very smooth, and a very high straightness and positioning accuracy can be obtained, and the speed inequality phenomenon is also improved. At the same time, due to the extremely low dust generation, the needs of sub-micron precision movement in a clean room environment can be met.

In addition, referring to FIG. 1 , through the operation of the two-limit switch 51 and the position sensor 52 installed on the guide rail unit 10 and the linear motor unit 40, the position of the slide unit 20 can be sensed, and the stroke and positioning of the slide unit 20 can be precisely controlled. The above components can all be centrally installed in the space between the bottom of the slide unit 20 and the guide rail unit 10.

In addition, the advantages of the present invention are summarized as follows:

1. The guide rail unit 10 of the present invention adopts a three-piece assembly design, which can be divided into a guide rail group consisting of the base 11 and two side seats 120, and combined with the design of the slide unit 20, this design method can reduce the stroke size requirements of ultra-precision grinding machine processing equipment, and the component design that can grind on all four sides is very suitable for the production of granite components, and can fully exert the precision capability of the plane grinding equipment, reducing the errors caused by side grinding, replacement of grinding wheels and disassembly and assembly of fixtures.

Second, each side end 211 and the corresponding side slider 23 and the lower slider 22 together form an inverted U-shaped side frame 25, and cooperate with the geometric form formed by the side seats 120 to further constrain the freedom of the slide unit 20, thereby realizing the ideal single-degree-of-freedom direction movement. The geometric constraint between the slide unit 20 and the guide rail assembly 12 is closed, so it can stably realize the ideal single linear degree of freedom constraint and meet the high-precision and high-stability movement requirements.

3. The pneumatic pressure bearing unit bearing 30 and air supply circuit design inside the slide unit 20. The pneumatic pressure bearing unit 30 is embedded (bonded) and integrated into the slide unit 20, evenly distributed between the slide unit 20 and the guide rail unit 10, and the corresponding hidden air guide duct assembly 24 is integrated and designed to make the appearance and periphery of the slide unit 20 more simple and unified, while effectively reducing the height of the slide unit 20.

4. The present invention uses precision granite as the main component, including the use of precision granite to make the guide rail unit 10. The main reason is that precision granite has the characteristics of low thermal conductivity (not easy to conduct heat), low thermal expansion coefficient (not easy to deform by heat), low density (light weight per volume), and good damping characteristics (high shock absorption ability). It is suitable for replacing metal materials and applied to semiconductor process equipment with extremely strict requirements on stability.

5. The guide rail unit 10 and the slide unit 20 of the present invention are composed of a simple rectangular shape and a split-piece design. The base 11 and the side seats 120 are composed of three-piece rectangular components, which are suitable for being made of stone. The rectangular components can be ground on all four sides due to their simple appearance, and the precision capability of the plane grinding equipment can be fully utilized. The stone material is mainly granite with high hardness (such as Indian black with the same hardness level or above), and is precisely ground to a flatness of DIN 876 00. The stability of the stone is higher than that of the sub-micrometer motion platform developed with the metal substrate (stainless steel, aluminum alloy) generally used. It has higher rigidity, reduces the flatness variation caused by the suspension of the moving parts, and can be used in semiconductor precision processing equipment. In addition, the slide unit 20 is composed of the base 21, the lower slide blocks 22, and the side slide blocks 23, and has a simple structure and is easy to process.

6. The present invention uses precision granite as the main structural component of the pneumatic hydrostatic motion platform device. The slide unit 20 uses the pneumatic hydrostatic buoyancy to perform non-contact sliding on the high-precision (flatness, straightness) granite guide rail set 12, and replaces the metal guide rail (linear slide rail made of stainless steel or aluminum alloy). In combination with the linear motor unit 40 (magnetic levitation), it can achieve high positioning accuracy and high acceleration and deceleration motion that is superior to metal rails, and can be applied to high-precision semiconductor wafer processing equipment.

As shown in FIG. 5 , the pneumatic hydrostatic motion platform device 100 of the above embodiment of the present invention can be stacked. Two uniaxially movable pneumatic hydrostatic motion platform devices are combined in a stacked manner to construct the required X-Y dual-axis motion platform movement and positioning functions, and are applied to high-precision processing equipment in the semiconductor and optoelectronic industries. The table size and movement stroke of the upper and lower motion tables can be adjusted in design according to the requirements of the equipment, and the guide rail assembly 12 or the entire motion platform can be modularized, graded, and interface standardized, which will help reduce mass production costs. In addition, customized designs can also be performed for special needs.

As shown in FIG6 , a second embodiment of the precision granite pneumatic hydrostatic motion platform device of the present invention is different from the first embodiment in that the guide rail unit 10 'is a two-piece type. It includes a base 11 ', and a guide rail assembly 12 'fixed to the base 11 '. The guide rail assembly 12 'is a single-piece type, and the guide rail assembly 12 'also has a recessed space 13 'recessed by the top surface, and the stator 41 of the linear motor unit 40 is installed in the recessed space 13 '. Two side seats 120 'are formed by the provision of the recessed space 13 '. The second embodiment can also achieve the same purpose and effect as the first embodiment.

As shown in FIG. 7 , a third embodiment of the precision granite pneumatic hydrostatic motion platform device of the present invention is different from the first embodiment in that the base 21 'of the slide unit 20 'also has an extension block 26 'set between the side seats 120, and the pneumatic hydrostatic bearing unit 30 also includes at least one fourth pneumatic hydrostatic bearing assembly 34 fixed to the extension block 26 'and opposite to the inner side surface 124 of one of the side seats 120. The third embodiment can also achieve the same purpose and effect as the above embodiment.

As shown in FIG8 , a fourth embodiment of the precision granite pneumatic hydrostatic motion platform device of the present invention is similar to the third embodiment, and the extension block 26' of the slide unit 20' is fixed with at least one fourth pneumatic hydrostatic bearing assembly 34 on opposite sides. The fourth embodiment can also achieve the same purpose and effect as the above embodiments.

In summary, the precision granite pneumatic hydrostatic motion platform device of the present invention has a simple overall structure, is easy to manufacture and assemble, and can achieve the purpose of precision processing, which can indeed achieve the purpose of this invention.

However, the above is only an example of the implementation of the present invention, and it cannot be used to limit the scope of the implementation of the present invention. All simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still within the scope of the patent of the present invention.

100: Hydrostatic motion platform device

10: Guide rail unit

11: Base

12: Guide rail assembly

120: Side seat

121: Top

122: Bottom

123: Outer side

124: Inner side

20: Sliding seat unit

21: Pedestal

211: Side end

212: Bottom end surface

213: First slot

22: Slide down block

221: Upper end surface

222: Second bezel

23: Side slider

231: Side surface

232: The third slot

24: Airway Group

241: First airway

242: Second airway

243: The third airway

25: Side frame

30: Hydrostatic bearing unit

31: The first hydrostatic bearing set

311: The first hydrostatic bearing

32: Second pneumatic hydrostatic bearing set

321: Second pneumatic hydrostatic bearing

33: The third hydrostatic bearing set

331: The third hydrostatic bearing

40: Linear motor unit

41: Stator

42: Movers

Y: horizontal axis

Claims (6)

A precision granite pneumatic hydrostatic motion platform device comprises: a guide rail unit, extending along a long axis and made of granite material, and comprising a base, and a guide rail assembly fixed to the base, the guide rail assembly having at least one top surface, two bottom surfaces opposite to the top surface, and two outer side surfaces intersecting the top surface and the bottom surface at an angle, the base and the guide rail assembly are composed of three-piece rectangular components; a slide unit, which can The slide unit slides on the guide rail unit along the long axis and includes a pedestal relative to the top surface, two lower slide blocks respectively relative to the bottom surfaces, two side slide blocks respectively connected between the pedestal and the lower slide blocks, and an air guide channel group connecting the pedestal, the lower slide blocks and the side slide blocks. The slide unit is composed of the pedestal, the lower slide blocks and the side slide blocks in a divided rectangular parallelepiped component. The side slide blocks are relative to the outer side surfaces. The pedestal has two side ends which are oppositely arranged along a transverse axis perpendicular to the long axis, and each side end and the corresponding side slider and the lower slider together form an inverted U-shaped side frame; a pneumatic pressure bearing unit is connected to the air guide assembly and includes a first pneumatic pressure bearing assembly fixed to the pedestal and opposite to the top surface, a second pneumatic pressure bearing assembly fixed to the lower sliders and opposite to the bottom surfaces, and a second pneumatic pressure bearing assembly fixed to the lower sliders and opposite to the bottom surfaces. The side sliders and the third pneumatic bearing set relative to the outer side surfaces, the pneumatic bearing unit can allow the generation of an air film between the slide unit and the guide rail unit; and a linear motor unit, including a stator mounted on the guide rail unit, and a mover mounted on the base of the slide unit and relative to the stator, the linear motor unit can drive the slide unit to produce linear movement relative to the guide rail unit along the long axis. The precision granite pneumatic pressure motion platform device as described in claim 1, wherein the base of the slide unit has a plurality of first embedded grooves, each of the lower slide blocks has a second embedded groove, each of the side slide blocks has a third embedded groove, the first pneumatic pressure bearing set of the pneumatic pressure bearing unit has a plurality of first pneumatic pressure bearings respectively embedded in the first embedded grooves, the second pneumatic pressure bearing set has a plurality of second pneumatic pressure bearings respectively embedded in the second embedded grooves, and the third pneumatic pressure bearing set has a plurality of third pneumatic pressure bearings respectively embedded in the third embedded grooves. As described in claim 2, the precision granite pneumatic hydrostatic motion platform device, wherein the first pneumatic hydrostatic bearing, the second pneumatic hydrostatic bearing and the third pneumatic hydrostatic bearing of the pneumatic hydrostatic bearing unit are made of porous materials. As described in claim 3, the precision granite pneumatic pressure motion platform device, wherein the first pneumatic pressure bearing, the second pneumatic pressure bearing and the third pneumatic pressure bearing of the pneumatic pressure bearing unit are made of porous ceramic material. The precision granite pneumatic hydrostatic motion platform device as described in claim 3, wherein the first pneumatic hydrostatic bearing, the second pneumatic hydrostatic bearing and the third pneumatic hydrostatic bearing of the pneumatic hydrostatic bearing unit are made of a material containing a porous graphite layer. The precision granite pneumatic hydrostatic motion platform device as described in claim 1, wherein the guide rail assembly of the guide rail unit is two-piece and also has two side seats spaced apart along the transverse axis, there are two top surfaces, one is disposed on each side seat, the bottom surfaces and the outer side surfaces are also disposed on the side seats, each side seat also has an inner side surface disposed opposite to the outer side surface, the platform has an extension block disposed between the side seats, and the pneumatic hydrostatic bearing unit also includes at least one fourth pneumatic hydrostatic bearing assembly fixed to the extension block and opposite to the inner side surface.