Desktop type photoetching machine lifting mechanism

Abstract

The invention discloses a desktop type photoetching machine lifting mechanism which comprises a lifting main frame, a rotary supporting plate is arranged on the periphery of the lifting main frame through a ball retainer assembly, a lead screw main shaft is arranged in the center of the lifting main frame through a bearing assembly, and a driving assembly connected with the lead screw main shaft is arranged on the lower portion of the lifting main frame. The upper portion of the lifting main frame is connected with a rotary fixing plate, a lifting bottom plate is arranged on the rotary fixing plate through a plurality of polished shaft assemblies arranged on the periphery, and the center of the lifting bottom plate is in threaded fit with a lead screw spindle through a lead screw structure. The precise lifting device has the beneficial effects that the modular and high-rigidity precise lifting device is provided, and the core design idea of layering and symmetrical layout is adopted for the device, so that the overall stability is ensured.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor manufacturing equipment, and particularly relates to a lifting mechanism of a desktop lithography machine, which is used for stably and accurately controlling the lifting of a substrate table during an exposure process. BACKGROUND

[0002] As a core technology in the field of semiconductor manufacturing and production, the precision and stability of the lithography technology directly determine the performance and quality of a device. In the manufacturing process of a semiconductor device, the lithography technology is used for lithographing a feature pattern on a workpiece surface, processing solder resist ink of a printed circuit board, and realizing punching processing for electrical interconnection between multi-layer circuit boards. The traditional lithography technology needs to make a mask master for exposure operation, and has problems such as long production cycle, single pattern, and limited application range. With the progress of technology, the direct writing lithography technology has gradually developed into an important processing direction, but the performance of the core worktable lifting system is still a key factor affecting the overall equipment precision.

[0003] In a desktop lithography machine with a compact structure, the lifting system faces more challenges: it needs to meet multiple requirements such as high precision, high stability, and small size. In the prior art, the parallelism adjustment of the worktable is also a technical difficulty, and how to ensure that the mask plate on the upper table panel is parallel to the wafer on the lower table panel directly affects the lithography precision. In addition, the traditional lifting type lithography machine worktable is difficult to be effectively combined with a conveying belt, which limits the continuous lithography processing of the PCB in a pipeline manner and affects the production efficiency.

[0004] Therefore, developing a high-stability and high-precision lifting structure suitable for a desktop lithography machine to solve the problems of insufficient stability, limited precision, short service life, and the like in the prior art has become a technical difficulty to be solved in the field. SUMMARY

[0005] The present application aims to solve the defects in the existing lifting system of a desktop lithography machine, including insufficient lifting stability, which causes the substrate table to easily vibrate or deviate during the exposure process, affecting the lithography precision; limited lifting precision, which is difficult to meet the requirements of nanometer lithography or high-resolution patterns; short service life of the device due to insufficient structural rigidity or wear, which requires frequent maintenance; and difficult adjustment of the parallelism of the worktable, which is difficult to ensure the parallelism between the mask plate and the wafer; in addition, the traditional device is difficult to be integrated with a conveying belt, which limits the continuous production efficiency. The present application provides a lifting mechanism of a desktop lithography machine, which overcomes the above problems and realizes stable, accurate, and durable lifting control.

[0006] The purpose of the present application is achieved by the following technical solutions: The application discloses a lifting mechanism of a desktop photoetching machine, which comprises a lifting main frame, a rotating support plate provided on the outer periphery of the lifting main frame through a ball retainer assembly, a screw main shaft provided on the center of the lifting main frame through a bearing assembly, a driving assembly connected with the screw main shaft and arranged on the lower part of the lifting main frame, a rotating fixed plate connected with the upper part of the lifting main frame, a lifting bottom plate provided on the rotating fixed plate through a plurality of optical axis assemblies arranged on the outer periphery of the rotating fixed plate, and a center of the lifting bottom plate is threadedly connected with the screw main shaft through a screw rod structure.

[0007] Further, the ball retainer assembly comprises axial ball retainers arranged on both sides of the rotating support plate in the axial direction and radial ball retainers arranged on the outer periphery of the lifting main frame and the inner periphery of the rotating support plate.

[0008] Further, the ball retainer assembly further comprises a locking sleeve and a locking block, the locking sleeve is sleeved on the outer periphery of the lifting main frame and located below the rotating support plate, axial ball retainers are arranged between the rotating support plate and the rotating fixed plate and between the rotating support plate and the locking sleeve, and the locking block is screwed on the outer periphery of the lifting main frame and located below the locking sleeve.

[0009] Further, the driving assembly comprises a servo motor and a shaft coupling, the servo motor is fixed on the lower part of the lifting main frame, and the output shaft of the servo motor is connected with the screw main shaft through the shaft coupling.

[0010] Further, the bearing assembly comprises a bearing stop ring, bearings and a bearing spacer, at least two bearings are arranged between the screw main shaft and the lifting main frame, the bearing spacer is arranged between the adjacent two bearings, and the bearing stop ring is screwed on the screw main shaft and located below the lowermost bearing.

[0011] Further, the optical axis assembly is provided with three optical axis bearings and arranged uniformly along the outer periphery.

[0012] Further, the optical axis assembly comprises optical axis bearings and optical axes, the optical axis bearings are arranged on the lifting bottom plate, the optical axis bearings are vertically sleeved on the optical axes, and the optical axes are arranged on the rotating fixed plate.

[0013] Further, the screw rod structure comprises a screw rod sleeve, the screw rod sleeve is located in the middle of the lifting bottom plate and threadedly connected with the threaded part of the screw main shaft. Further, the screw rod structure further comprises a rod sleeve pressing block, the screw rod sleeve is clamped between the lifting bottom plate and the rod sleeve pressing block, and the lifting bottom plate, the screw rod sleeve and the rod sleeve pressing block are connected into an integrated whole through bolts.

[0014] Further, the rotating support plate is arranged on the mounting plate assembly.

[0015] The beneficial effects of this application are: it provides a modular, high-rigidity precision lifting device, which adopts a layered and symmetrical layout as its core design concept to ensure overall stability.

[0016] The aforementioned main solution and its various further alternatives can be freely combined to form multiple solutions, all of which are solutions that can be adopted and claimed in this application; furthermore, the (non-conflicting alternatives) can also be freely combined with each other and with other alternatives. Those skilled in the art, after understanding this solution, will realize from the prior art and common general knowledge that there are many combinations, all of which are technical solutions to be protected in this application, and will not be exhaustively listed here. Attached Figure Description

[0017] Figure 1 This is a structural cross-sectional view of this application.

[0018] Figure 2 This is a three-dimensional structural view of this application.

[0019] In the diagram: 1-Screw spindle; 2-Screw sleeve; 3-Lifting base plate; 4-Rotating fixed plate; 5-Axial ball retainer; 6-Rotating support plate; 7-Radial roller retainer; 8-Locking ring; 9-Locking block; 10-Lifting main frame; 11-Servo motor; 12-Coupling; 13-Bearing retaining ring; 14-Bearing; 15-Bearing spacer; 16-Optical shaft bearing; 17-Optical shaft; 18-Sleeve pressure block; 19-Mounting plate assembly. Detailed Implementation

[0020] The present application will be further described below with reference to specific embodiments and accompanying drawings.

[0021] Example 1 refer to Figure 1 and Figure 2 As shown, a desktop lithography machine lifting mechanism includes a lead screw spindle 1, a lifting base plate 3, a rotating fixed plate 4, a rotating support plate 6, a lifting main frame 10, a ball bearing cage assembly, a drive assembly, a bearing assembly, an optical shaft assembly, and a lead screw structure. The core of this lifting mechanism lies in achieving smooth and precise lifting motion of the worktable (substrate stage) through a precision mechanical transmission and guiding system.

[0022] The upper part of the lifting main frame 10 is connected to the lower part of the rotating fixed plate 4. The rotating fixed plate 4 and the lifting main frame 10 are connected as a whole by screws to form the main body of the mechanism, which is used to support or install other parts and components. The outer periphery of the lifting main frame 10 is provided with a rotating support plate 6 through a ball bearing retainer assembly. The rotating support plate 6 can be fixed on the mounting plate assembly, so that the internal main body of the mechanism can perform micro-leveling movements through the spherical pair formed by the ball bearing retainer.

[0023] A lead screw spindle 1 is mounted at the center of the lifting main frame 10 via a bearing assembly, enabling the lead screw spindle 1 to rotate along the vertical axis. A drive assembly connected to the lead screw spindle 1 is located at the lower part of the lifting main frame 10, providing power for the rotation of the lead screw spindle 1.

[0024] A lifting base plate 3 is mounted on the rotating fixed plate 4 via several optical axis assemblies arranged around its outer periphery. The optical axis assemblies guide and position the lifting base plate 3 to ensure precise and stable lifting. The center of the lifting base plate 3 is threadedly connected to the lead screw spindle 1 via a lead screw structure. Thus, the rotational motion of the lead screw spindle 1 is converted into the up-and-down lifting motion of the lifting base plate 3 through the lead screw structure.

[0025] The lifting base plate 3 is used to drag the overall upper photolithography structure. This lifting mechanism performs the function of lifting control. The basic structure must ensure the strength and rigidity of the device, and the assembly error of the device must be ensured through the details of component processing. During the photolithography process, the stability of the lifting top photolithography platform must also be ensured. Precision control is achieved through the detailed design of the axis system.

[0026] Example 2 refer to Figure 1 and Figure 2 As shown, a desktop lithography machine lifting mechanism is an extension of Embodiment 1.

[0027] The ball cage assembly includes an axial ball cage 5 and a radial ball cage 7. The axial ball cage 5 is located on both sides of the rotating support plate 6 in the axial direction, and the radial ball cage 7 is located on the outer periphery of the lifting main frame 10 and the inner periphery of the rotating support plate 6. The axial and radial ball cages together form a low-friction, micro-rotational spherical pair, which enables micro-leveling of the mechanism.

[0028] The ball retainer assembly also includes a locking ring 8 and a locking block 9. The locking ring 8 is sleeved on the outer periphery of the lifting main frame 10 and located below the rotating support plate 6. Axial ball retainers 5 are provided between the rotating support plate 6 and the rotating fixed plate 4, and between the rotating support plate 6 and the locking ring 8. The locking block 9 is screwed to the outer periphery of the lifting main frame 10 and located below the locking ring 8.

[0029] By adjusting the tightness of the locking block 9, the mounting plate assembly can be allowed to rotate slightly relative to the lifting base plate 3, thereby precisely adjusting the levelness (i.e., parallelism) of the worktable plane and ensuring that the mask is strictly parallel to the wafer during exposure.

[0030] The drive assembly includes a servo motor 11 and a coupling 12. The servo motor 11 is fixed to the lower part of the lifting main frame 10, and provides power for the rotation of the lead screw spindle 1. The output shaft of the servo motor 11 is connected to the lead screw spindle 1 through the coupling 12. The high-precision coupling 12 realizes the transmission of rotation, transmitting the rotational motion of the servo motor 11 to the lead screw spindle 1.

[0031] The bearing assembly includes a bearing retaining ring 13, a bearing 14, and a bearing spacer 15. At least two bearings 14 are disposed between the lead screw spindle 1 and the lifting main frame 10 to realize the rotational support function of the lifting main frame 10 on the lead screw spindle 1. It is preferable to use two bearings 14, which has the advantages of high support accuracy and can also realize the miniaturization of the mechanism.

[0032] A bearing spacer 15 is provided between two adjacent bearings 14. The bearing spacer 15 is also located between the lead screw spindle 1 and the lifting main frame 10, but the inner side of the bearing spacer 15 does not contact the lead screw spindle 1 to avoid friction. The bearing spacer 15 realizes the spaced arrangement of the bearings 14 to ensure that the rotational support is evenly distributed.

[0033] The bearing retainer ring 13 is screwed onto the lead screw spindle 1 and located below the lowest bearing 14. The bearing retainer ring 13 axially limits all bearings 14, preventing them from falling off under gravity. The bearing retainer ring 13, bearings 14, and bearing spacer ring 15 together ensure the radial and axial stability of the lead screw spindle 1 during rotation, reducing runout.

[0034] The optical axis assembly has three components, which are evenly arranged along the outer perimeter to ensure that the lifting base plate 3 has extremely high rigidity and stability during the lifting process and avoids lateral swaying.

[0035] The optical axis assembly includes optical axis bearings 16 and optical axes 17. The optical axis bearings 16 are fixedly mounted on the lifting base plate 3, and three optical axis bearings 16 are evenly arranged along the outer periphery of the lifting base plate 3. The optical axes 17 are fixed to the rotating fixed plate 4 by screws, and the three optical axes 17 are evenly and vertically mounted on the rotating fixed plate 4 along its outer periphery. The optical axis bearings 16 are vertically sleeved on the optical axes 17. When the lifting base plate 3 moves under the drive of the lead screw, the three optical axes 17 slide within their respective optical axis bearings 16, forming a precise guide with three-point support, greatly enhancing the torsional rigidity and linearity of the entire lifting structure.

[0036] The lead screw structure includes a lead screw sleeve 2 and a sleeve pressure block 18. The lead screw sleeve 2 is located in the middle of the lifting base plate 3 and is threadedly engaged with the threaded part of the lead screw spindle 1. The key to realizing the lifting function is to convert the rotational motion of the lead screw spindle 1 into linear motion. The lead screw sleeve 2 is precisely engaged with the threaded part of the lead screw spindle 1. When the lead screw rotates, the lead screw sleeve 2 will move along the lead screw axis. At the same time, the lead screw sleeve 2 is fixedly connected to the lifting base plate 3. Therefore, the lifting base plate 3 will move vertically in a linear motion together with the lead screw sleeve 2.

[0037] The outer edge of the lead screw sleeve 2 is clamped between the lifting base plate 3 and the sleeve pressure block 18. The collar of the lead screw sleeve 2 passes through the center hole of the lifting base plate 3. The sleeve pressure block 18 is a ring plate sleeved on the lead screw spindle 1. The lifting base plate 3, the lead screw sleeve 2 and the sleeve pressure block 18 are connected as one piece by bolts, thereby fixing the lead screw sleeve 2 on the lifting base plate 3.

[0038] The rotating support plate 6 is mounted on the mounting plate assembly 19. With the rotating support plate 6 as the boundary, the lower part of the mechanism is located inside the mounting plate assembly 19, so as to achieve safe, stable and reliable operation. The upper part of the mechanism (including the rotating support plate 6) is located outside the mounting plate assembly 19 (upper part), and performs the specific movement function of lifting and lowering, so as to drive the photolithography structure outside (upper part) to move synchronously.

[0039] The workflow of this application is as follows: The servo motor 11 receives a control signal and drives the lead screw spindle 1 to rotate precisely through the coupling 12, thereby driving the lead screw sleeve 2 and the connected lifting base plate 3 to rise and fall smoothly along the direction defined by the three optical axes 17. The movement of the lifting base plate 3 is transmitted to the top worktable through the leveling mechanism composed of the rotating support plate 6 and the ball bearing retainer, ultimately achieving precise positioning of the worktable that carries the wafer.

[0040] The entire device has a compact structure, with the main driving force provided by the lead screw spindle, the three-axis guiding system ensuring rigidity, and the spherical pair leveling mechanism compensating for parallelism errors. Together, they meet the high stability and high precision lifting requirements suitable for desktop lithography machines.

[0041] The foregoing basic examples and their further alternative examples can be freely combined to form multiple embodiments, all of which are embodiments that can be adopted and claimed in this application. In the scheme of this application, each alternative example can be arbitrarily combined with any other basic example and alternative example.

[0042] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lifting mechanism for a desktop lithography machine, comprising a lifting main frame (10), characterized in that: The outer periphery of the lifting main frame (10) is provided with a rotating support plate (6) through a ball retainer assembly. The center of the lifting main frame (10) is provided with a lead screw spindle (1) through a bearing assembly. The lower part of the lifting main frame (10) is provided with a drive assembly connected to the lead screw spindle (1). The upper part of the lifting main frame (10) is connected to a rotating fixed plate (4). The rotating fixed plate (4) is provided with a lifting base plate (3) through several optical shaft assemblies arranged on the outer periphery. The center of the lifting base plate (3) is threadedly engaged with the lead screw spindle (1) through a lead screw structure.

2. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The ball retainer assembly includes an axial ball retainer (5) and a radial ball retainer (7). The axial ball retainer (5) is located on both sides of the rotating support plate (6) in the axial direction, and the radial ball retainer (7) is located on the outer periphery of the lifting main frame (10) and the inner periphery of the rotating support plate (6).

3. The desktop lithography machine lifting mechanism according to claim 2, characterized in that: The ball retainer assembly further includes a locking collar (8) and a locking block (9). The locking collar (8) is sleeved on the outer periphery of the lifting main frame (10) and located below the rotating support plate (6). An axial ball retainer (5) is provided between the rotating support plate (6) and the rotating fixed plate (4) and between the rotating support plate (6) and the locking collar (8). The locking block (9) is screwed to the outer periphery of the lifting main frame (10) and located below the locking collar (8).

4. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The drive assembly includes a servo motor (11) and a coupling (12). The servo motor (11) is fixed to the lower part of the lifting main frame (10), and the output shaft of the servo motor (11) is connected to the lead screw spindle (1) through the coupling (12).

5. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The bearing assembly includes a bearing retainer (13), a bearing (14) and a bearing spacer (15). At least two bearings (14) are located between the lead screw spindle (1) and the lifting main frame (10). A bearing spacer (15) is provided between two adjacent bearings (14). The bearing retainer (13) is screwed onto the lead screw spindle (1) and located below the lowest bearing (14).

6. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The optical axis assembly has three components, which are evenly arranged along the outer periphery.

7. The desktop lithography machine lifting mechanism according to claim 1 or 6, characterized in that: The optical axis assembly includes an optical axis bearing (16) and an optical axis (17). The optical axis bearing (16) is mounted on the lifting base plate (3), and the optical axis bearing (16) is vertically mounted on the optical axis (17). The optical axis (17) is mounted on the rotating fixed plate (4).

8. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The screw structure includes a screw sleeve (2), which is located in the middle of the lifting base plate (3) and is threadedly engaged with the threaded part of the screw spindle (1).

9. The desktop lithography machine lifting mechanism according to claim 8, characterized in that: The screw structure also includes a sleeve pressure block (18). The screw sleeve (2) is sandwiched between the lifting base plate (3) and the sleeve pressure block (18). The lifting base plate (3), the screw sleeve (2) and the sleeve pressure block (18) are connected as a whole by bolts.

10. The desktop lithography machine lifting mechanism according to claim 1, characterized in that: The rotating support plate (6) is mounted on the mounting plate assembly (19).

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