Device and method for preparing quartz material with extremely optical uniformity

Abstract

The invention relates to the technical field of quartz material preparation, and particularly discloses a device and method for preparing a quartz material with extremely optical uniformity, the device comprises a groove sinking furnace supporting base frame and a groove sinking furnace, the top of the groove sinking furnace supporting base frame is provided with a top frame, and the bottom of the groove sinking furnace supporting base frame is provided with a base; an electric telescopic rod is installed in the middle of the top frame, a first rotating motor is installed at the telescopic end of the electric telescopic rod, a first weighing device is installed on a main shaft of the first rotating motor, and a connecting rod is fixedly connected to the bottom of the first weighing device; one end of the connecting rod penetrates through the furnace cover and the heater at the top end in the groove sinking furnace, the defects of existing equipment are overcome, and a quartz material prepared in a groundbreaking uniform feeding mode can be directly used as a photoetching machine lens, a 248nm photoetching projection objective lens system and other high-end optical elements.

Description

Technical Field

[0001] The invention relates to the technical field of quartz material preparation, and in particular to a device and method for preparing a quartz material with extremely high optical uniformity. Background Art

[0002] Quartz has excellent optical properties such as high purity, high transmittance, good uniformity, low stress, no streaks, no particle structure, no bubbles, no inclusions, no fluorescence, and resistance to laser damage. It is the preferred material for 248nm and 193nm band lithography systems. The requirements for lithography-grade quartz materials are extremely high. Its optical uniformity alone needs to be within 1.0×10 -7 Optical uniformity is an important indicator of the optical quality of quartz materials. It indicates the degree of uniformity of the refractive index inside the isotropic medium. When light passes through an inhomogeneous medium, the wavefront will be distorted, and the magnitude of the distortion depends on the product of the refractive index difference and the thickness. The optical uniformity of optical quartz refers to the inconsistency of the refractive index inside the same piece of optical glass, and is often expressed by the maximum difference in the refractive index inside it. Optical uniformity is a very important glass quality indicator. It directly affects the wavefront quality of the transmission optical system and changes the wave aberration of the system, which will cause the optical system to fail to achieve the expected function or even fail to work properly. As an essential optical component material for various high-precision optical systems, the optical uniformity of quartz glass directly affects the imaging quality of the optical system. The high quality of optical materials is reflected in their uniformity. More specifically, the refractive index variation range of the entire material is extremely narrow.

[0003] In foreign countries, a certain proportion of extremely optically uniform quartz can be directly obtained by multi-torch deposition. In order to obtain extremely optically uniform quartz products that meet actual use, the industry usually first deposits CVD to obtain highly uniform synthetic quartz ingots, and then reshapes and homogenizes them through secondary trough sinking to ensure the requirements of extremely optical uniformity. The trough sinking process is mainly divided into two categories: load forming and no-load forming. Load means adding a pressure plate at the top of the product to squeeze it under high temperature by external force, and no-load means softening and spreading it to a larger size under high temperature without external force but only by its own weight.

[0004] Direct deposition by multiple torches has the characteristics of complex process, difficult control, need for optimal area and poor consistency of indicators. Load-type trough sedimentation has high success rate and high efficiency, but it is difficult to obtain materials with high optical uniformity. Non-load trough sedimentation can achieve the preparation of highly uniform quartz materials, but it is still difficult to achieve extremely optical uniformity. Therefore, a device and method for preparing quartz materials with extremely optical uniformity are provided. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for preparing a quartz material with extremely high optical uniformity in view of the defects of the prior art, so as to solve the problems raised by the above-mentioned background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a device for preparing quartz material with extremely high optical uniformity, comprising a slot sink furnace supporting base frame and a slot sink furnace, wherein a top frame is installed on the top of the slot sink furnace supporting base frame, a base is installed on the bottom of the slot sink furnace supporting base frame, an electric telescopic rod is installed in the middle of the top frame, a first rotating motor is installed at the telescopic end of the electric telescopic rod, a first weighing device is installed on the main shaft of the first rotating motor, and a connecting rod is fixedly connected to the bottom of the first weighing device; one end of the connecting rod passes through the furnace cover and the heater at the top of the inside of the slot sink furnace, and is fixedly connected to the slot sink masterbatch clamp; heaters are installed on the inner peripheral side, top and bottom of the slot sink furnace, a base is installed on the bottom of the slot sink furnace supporting base frame, a second weighing device is installed at the center position of the base, a second rotating motor is installed on the top of the second weighing device, one end of the main shaft of the second rotating motor passes through the bottom of the slot sink furnace, and is fixedly connected to the slot sink crucible mold inside the slot sink furnace.

[0007] As a preferred technical solution of the present invention, the top frame and the base are both welded to the trough sink furnace support base frame, and the trough sink furnace and the trough sink furnace support base frame are fixedly connected by bolts.

[0008] As a preferred technical solution of the present invention, the electric telescopic rod is installed at the center position of the top frame by bolts, the housing of the first rotating motor is fixedly connected to the telescopic end of the electric telescopic rod by bolts, and the first weighing device is installed on the main shaft of the first rotating motor by bolts.

[0009] As a preferred technical solution of the present invention, the connecting rod is welded to the groove sinking masterbatch fixture, and the groove sinking masterbatch is installed in the groove sinking masterbatch fixture.

[0010] As a preferred technical solution of the present invention, the heater at the top of the trough furnace is installed on the bottom of the furnace cover by bolts, the heater at the bottom of the trough furnace is installed on the bottom of the trough furnace by bolts, and the heater on the peripheral side of the trough furnace is installed on the inner wall of the trough furnace by bolts.

[0011] As a preferred technical solution of the present invention, both the first weighing device and the second weighing device are electronic scales, and the second rotating motor is fixedly connected to the second weighing device.

[0012] As a preferred technical solution of the present invention, the electric telescopic rod, the first weighing device, the second rotating motor, the second weighing device, and the first rotating motor are all connected to the PLC control box via an electronic signal transmission line.

[0013] A method for preparing a quartz material with extremely high optical uniformity is implemented by using a quartz material preparation device with extremely high optical uniformity, and the specific steps are as follows:

[0014] Step 1: First, clamp and fix the upper end of the trough sinking masterbatch on the trough sinking masterbatch fixture, and ensure that the lower end of the trough sinking masterbatch is at a distance of more than mm from the inner upper surface of the trough sinking crucible mold through an electric telescopic rod;

[0015] Step 2: The bottom and circumferential heaters of the trough sinking furnace are operated to preheat the furnace to the working temperature according to the process requirements, and the trough sinking masterbatch is evenly lowered by the electric telescopic rod until it slightly contacts the upper surface of the inner part of the trough sinking crucible mold. At this time, the second weighing device measures the weight of the trough sinking masterbatch and displays the weight reading ΔW;

[0016] Step 3: Setting the first rotating motor and the second rotating motor to rotate in the same direction at the same speed through the PLC control box;

[0017] Step 4: The bottom of the trough sinking masterbatch softens and spreads out under high temperature conditions. During the spreading process, the first weighing device detects the online weight of the trough sinking masterbatch in real time through the connecting rod, and the second weighing device monitors the weight of the material inside the trough sinking crucible mold in real time;

[0018] Step 5: Control the speed of the electric telescopic rod's automatic descent through the PLC control box to ensure that the weight increase value of the second weighing device per unit time is consistent;

[0019] Step 6: When the second weighing device weighs close to the original weight of the trough sinking masterbatch, turn on the heater on the top of the trough sinking furnace to make the temperature reach the temperature specified by the process, so that the top can be homogenized faster and better.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1: The trough sink furnace is equipped with heaters at the bottom, circumference and top to achieve the temperature control requirements in steps. In the early and middle stages of the softening of the trough sink masterbatch, the bottom and circumference heaters are mainly used to ensure that the furnace has a suitable gradual temperature reduction effect from bottom to top, and the bottom of the masterbatch is softened first to drive the upper material; in the middle and late stages, the bottom, circumference and top are kept at the same temperature to achieve better homogenization of the material.

[0022] 2: The trough sink furnace is limited by equipment conditions, and the best temperature uniformity under large-scale conditions is ±3-5°C. During the high-temperature softening process of the trough sink masterbatch, it will first creep toward the high-temperature zone, causing asymmetric spreading and thus affecting the uniformity index. The present invention solves the impact of different temperature fields of trough sink softening by maintaining consistent rotation of the mold rotation system (second rotating motor) and the material rotation system (first rotating motor).

[0023] 3: During the sinking process, the material lifting system (electric telescopic rod) is controlled by PLC central control to automatically lower the sinking speed of the masterbatch, ensuring that the weight increase of the weighing system per unit time is consistent, effectively solving the problem that the conventional no-load sinking has a large initial load-bearing capacity, a smaller load-bearing capacity in the middle and late stages, and uneven forces between layers.

[0024] 4: The present invention provides a device and method for preparing quartz materials with extremely high optical uniformity, which solves the defects of existing equipment. The quartz materials prepared by the innovative uniform feeding method can be directly used as high-end optical components such as lithography machine lenses and 248nm lithography projection objective systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the present invention.

[0026] In the figure: 1. electric telescopic rod; 2. first weighing device; 3. connecting rod; 4. trough sinking furnace; 5. heater; 6. second rotating motor; 7. second weighing device; 8. PLC control box; 9. trough sinking crucible mold; 10. trough sinking masterbatch; 11. first rotating motor; 12. trough sinking masterbatch fixture; 13. trough sinking furnace supporting base frame; 14. electronic signal transmission line; 15. top frame; 16. base; 17. furnace cover. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0028] Example: See Figure 1 The present invention provides a technical solution: a device for preparing quartz material with extremely high optical uniformity, comprising a trough sink furnace support base frame 13 and a trough sink furnace 4, a top frame 15 is installed on the top of the trough sink furnace support base frame 13, a base 16 is installed on the bottom of the trough sink furnace support base frame 13, an electric telescopic rod 1 is installed in the middle of the top frame 15, and the electric telescopic rod 1 is used to realize the up and down movement of the trough sink master material clamp 12, a first rotating motor 11 is installed at the telescopic end of the electric telescopic rod 1, and the first rotating motor 11 can drive the trough sink master material 10 to rotate, a first weighing device 2 is installed on the main shaft of the first rotating motor 11, and the trough sink master material 10 is weighed, and the bottom of the first weighing device 2 is fixedly connected with a connecting rod 3; connecting One end of the rod 3 passes through the furnace cover 17 and the heater 5 at the top of the trough sinking furnace 4, and is fixedly connected to the trough sinking masterbatch clamp 12; heaters 5 are installed on the inner circumference, top and bottom of the trough sinking furnace 4 to ensure that the furnace has a suitable gradual temperature reduction effect from bottom to top, and a base 16 is installed at the bottom of the trough sinking furnace support base 13. A second weighing device 7 is installed at the center of the base 16 to weigh the trough sinking masterbatch 10 in the trough sinking crucible mold 9. A second rotating motor 6 is installed on the top of the second weighing device 7. One end of the main shaft of the second rotating motor 6 passes through the bottom of the trough sinking furnace 4 and is fixedly connected to the trough sinking crucible mold 9 inside the trough sinking furnace 4. The second rotating motor 6 is used to drive the trough sinking crucible mold 9 to rotate.

[0029] The top frame 15 and the base 16 are both connected by welding to the trough sink furnace support base frame 13, and the trough sink furnace 4 is fixedly connected to the trough sink furnace support base frame 13 by bolts.

[0030] The electric telescopic rod 1 is installed at the center of the top frame 15 by bolts, the housing of the first rotary motor 11 is fixedly connected to the telescopic end of the electric telescopic rod 1 by bolts, and the first weighing device 2 is installed on the main shaft of the first rotary motor 11 by bolts.

[0031] The connecting rod 3 is connected to the groove sinking masterbatch fixture 12 by welding, and the groove sinking masterbatch fixture 12 is installed with the groove sinking masterbatch 10.

[0032] The heater 5 at the top of the trough sink furnace 4 is installed on the bottom of the furnace cover 17 by bolts, the heater 5 at the bottom of the trough sink furnace 4 is installed on the bottom of the trough sink furnace 4 by bolts, and the heater 5 on the peripheral side of the trough sink furnace 4 is installed on the inner wall of the trough sink furnace 4 by bolts.

[0033] The first weighing device 2 and the second weighing device 7 are both electronic scales, and the second rotating motor 6 is fixedly connected to the second weighing device 7 .

[0034] The electric telescopic rod 1 , the first weighing device 2 , the second rotating motor 6 , the second weighing device 7 , and the first rotating motor 11 are all connected to the PLC control box 8 via an electronic signal transmission line 14 .

[0035] A method for preparing a quartz material with extremely high optical uniformity is implemented by using a quartz material preparation device with extremely high optical uniformity, and the specific steps are as follows:

[0036] Step 1: First, the upper end of the trough sinking masterbatch 10 is clamped and fixed on the trough sinking masterbatch fixture 12, and the lower end of the trough sinking masterbatch 10 is ensured to be more than 5 mm away from the inner upper surface of the trough sinking crucible mold 9 through the electric telescopic rod 1;

[0037] Step 2: The bottom and circumferential heaters 5 of the trough sinking furnace 4 are operated to preheat the furnace to the working temperature according to the process requirements, and the trough sinking masterbatch 10 is evenly lowered by the electric telescopic rod 1 until it slightly contacts the upper surface of the inner part of the trough sinking crucible mold 9. At this time, the second weighing device 7 measures the weight of the trough sinking masterbatch 10 and displays the weight reading ΔW;

[0038] Step 3: Set the first rotating motor 11 and the second rotating motor 6 to rotate in the same direction at the same rotation speed through the PLC control box 8;

[0039] Step 4: The bottom of the trough sinking masterbatch 10 softens and spreads out under high temperature conditions. During the spreading process, the first weighing device 2 detects the online weight of the trough sinking masterbatch 10 in real time through the connecting rod 3, and the second weighing device 7 monitors the weight of the material inside the trough sinking crucible mold 9 in real time;

[0040] Step 5: Control the speed of automatic descent of the electric telescopic rod 1 through the PLC control box 8 to ensure that the weight increase value of the second weighing device 7 per unit time is consistent;

[0041] Step 6: When the second weighing device 7 weighs and displays a value close to the original weight of the tank sinking masterbatch 10, the heater 5 on the upper part of the tank sinking furnace 4 is turned on to make the temperature reach the temperature specified by the process, so that the upper part can be homogenized faster and better;

[0042] Step 7: For the above quartz performance test and determination, the comparison indicators of different process conditions are shown in the following table:

[0043]

[0044] In summary, the trough sink furnace of the present invention is provided with heaters at the bottom, circumference and top, which can realize the temperature control requirements in steps. In the early and middle stages of the softening of the trough sink masterbatch, the bottom and circumference heaters are mainly used to ensure a suitable gradual temperature reduction effect from bottom to top in the furnace, and the bottom of the masterbatch is softened first to drive the upper layer of materials; in the middle and late stages, the bottom, circumference and top are kept at the same temperature to achieve better homogenization of the materials.

[0045] The present invention solves the influence of different temperature fields of tank sink softening by maintaining consistent and unidirectional rotation of the mold rotating system (second rotating motor) and the material rotating system (first rotating motor).

[0046] During the trough sinking process, the material lifting system (electric telescopic rod) is controlled by PLC centralized control to automatically lower the trough sinking masterbatch speed, ensuring the consistent weight increase of the weighing system per unit time. This effectively solves the problem of conventional no-load trough sinking having a large initial load-bearing capacity, a decreasing load-bearing capacity in the middle and late stages, and uneven forces between layers.

[0047] The present invention provides a device and method for preparing quartz material with extremely high optical uniformity, which solves the defects of existing equipment. The quartz material prepared by the innovative uniform feeding method can be directly used as high-end optical components such as lithography machine lenses and 248nm lithography projection objective systems.

[0048] The above embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A device for preparing quartz material with extremely high optical uniformity, comprising a trough sink furnace support frame (13) and a trough sink furnace (4), characterized in that: A top frame (15) is installed on the top of the trough sink furnace support base frame (13), a base (16) is installed on the bottom of the trough sink furnace support base frame (13), an electric telescopic rod (1) is installed in the middle of the top frame (15), a first rotating motor (11) is installed on the telescopic end of the electric telescopic rod (1), a first weighing device (2) is installed on the main shaft of the first rotating motor (11), and a connecting rod (3) is fixedly connected to the bottom of the first weighing device (2); one end of the connecting rod (3) passes through the furnace cover (17) and the top of the inner part of the trough sink furnace (4) The heater (5) is fixedly connected to the trough sinking masterbatch fixture (12); the heater (5) is installed on the inner circumference, top and bottom of the trough sinking furnace (4); a base (16) is installed at the bottom of the trough sinking furnace support base frame (13); a second weighing device (7) is installed at the center of the base (16); a second rotating motor (6) is installed on the top of the second weighing device (7); one end of the main shaft of the second rotating motor (6) passes through the bottom of the trough sinking furnace (4) and is fixedly connected to the trough sinking crucible mold (9) inside the trough sinking furnace (4).

2. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The top frame (15) and the base (16) are both connected by welding to the trough sink furnace support base frame (13), and the trough sink furnace (4) is fixedly connected to the trough sink furnace support base frame (13) by bolts.

3. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The electric telescopic rod (1) is mounted on the center position of the top frame (15) by means of bolts, the housing of the first rotating motor (11) is fixedly connected to the telescopic end of the electric telescopic rod (1) by means of bolts, and the first weighing device (2) is mounted on the main shaft of the first rotating motor (11) by means of bolts.

4. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The connecting rod (3) is connected to the groove sinking masterbatch fixture (12) by welding, and the groove sinking masterbatch fixture (12) has the groove sinking masterbatch (10) installed inside.

5. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The heater (5) at the top of the trough sink furnace (4) is mounted on the bottom of the furnace cover (17) by bolts, the heater (5) at the bottom of the trough sink furnace (4) is mounted on the bottom of the trough sink furnace (4) by bolts, and the heater (5) at the circumferential side of the trough sink furnace (4) is mounted on the inner wall of the trough sink furnace (4) by bolts.

6. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The first weighing device (2) and the second weighing device (7) are both electronic scales, and the second rotating motor (6) is fixedly connected to the second weighing device (7).

7. The device for preparing a quartz material with extremely high optical uniformity according to claim 1, characterized in that: The electric telescopic rod (1), the first weighing device (2), the second rotating motor (6), the second weighing device (7), and the first rotating motor (11) are all connected to the PLC control box (8) via an electronic signal transmission line (14).

8. A method for preparing a quartz material with extremely high optical uniformity, characterized in that: The method is implemented by using the device for preparing the extremely optically uniform quartz material according to any one of claims 1 to 7, and the specific steps are as follows: Step 1: First, the upper end of the trough sinking masterbatch (10) is clamped and fixed on the trough sinking masterbatch fixture (12), and the lower end of the trough sinking masterbatch (10) is ensured to be at least 5 mm away from the inner upper surface of the trough sinking crucible mold (9) through an electric telescopic rod (1); Step 2: The bottom and circumferential heaters (5) of the trough sinking furnace (4) are operated to preheat the furnace to the working temperature according to the process requirements, and the trough sinking masterbatch (10) is evenly lowered by the electric telescopic rod (1) until it slightly contacts the inner upper surface of the trough sinking crucible mold (9). At this time, the second weighing device (7) measures the weight of the trough sinking masterbatch (10) and displays the weight reading ΔW; Step 3: Setting the first rotating motor (11) and the second rotating motor (6) to rotate in the same direction at the same rotation speed through the PLC control box (8); Step 4: The bottom of the trough sinking masterbatch (10) softens and spreads out under high temperature conditions. During the spreading process, the first weighing device (2) detects the online weight of the trough sinking masterbatch (10) in real time through the connecting rod (3), and the second weighing device (7) monitors the weight of the material inside the trough sinking crucible mold (9) in real time; Step 5: Control the speed of the automatic descent of the electric telescopic rod (1) through the PLC control box (8) to ensure that the weight increase value of the second weighing device (7) per unit time is consistent; Step 6: When the second weighing device (7) weighs and displays a weight close to the original weight of the tank sinking masterbatch (10), turn on the heater (5) on the top of the tank sinking furnace (4) to make the temperature reach the temperature specified by the process, so that the top can be homogenized faster and better.

Images