Full-automatic multi-station drying device for semiconductor wafer

Abstract

The utility model discloses a full-automatic multi-station drying device for semiconductor wafers, and relates to the technical field of semiconductor manufacturing equipment. The device comprises symmetrically arranged base plates, a conveying platform between the base plates, and a drying cabin mounted in the middles of the base plates. The drying cabin body is divided into a pretreatment area, a main drying area and a cooling area through four sets of lifting type isolation doors, and channels are formed in the bottoms of the isolation doors and driven by independent motors. An infrared radiation heating array is arranged on the inner wall of the main drying area, and an air cooling hole channel communicated with a cooling fan is formed in the inner wall of the cooling area. The material transfer trolley slides on the conveying platform through a guide rail, and a bearing bracket of the material transfer trolley is provided with a wedge-shaped locking block driven by a double-torsion spring and used for locking a wafer carrying disc with a conical positioning boss. The propelling mechanism enables the push rod to be matched with the positioning support to achieve automatic transfer of the transfer trolley. According to the utility model, the full-flow closed automatic operation of wafer drying-cooling is realized, the problem of temperature fluctuation is solved, and the yield is improved by more than 15%.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing equipment technology, specifically a multi-station integrated, temperature-controlled fully automatic wafer drying device. Background Technology

[0002] Semiconductor wafers, as the core substrate for integrated circuit manufacturing, require micron-level circuit structures to be formed on their surface. If trace amounts of moisture or chemical reagents remain after wet etching and cleaning processes on these precision devices, and are not completely removed, it will lead to defects such as oxidation of metal circuits and cracking of dielectric layers, directly affecting chip yield.

[0003] However, the current semiconductor drying process has the following main drawbacks:

[0004] 1. Temperature control imbalance - Traditional hot air drying is prone to creating temperature gradients, and uneven heating of wafers in some areas can cause structural stress deformation;

[0005] 2. Particulate contamination risk—Environmental particles adhere to the wafer surface during open transmission, causing physical damage to the patterned area;

[0006] 3. Low level of automation - manual transfer of wafer carriers leads to process interruption, low conversion efficiency of drying-cooling process, and high temperature exposure increases the probability of human contamination. Utility Model Content

[0007] 1. Technical problem to be solved:

[0008] In view of the problems of large temperature fluctuations, high risk of cross-contamination and poor process continuity in the existing technology, the purpose of this utility model is to provide a fully automatic multi-station drying device for semiconductor wafers, which can realize the core functions of precise temperature control in zones, closed-loop automated transmission and zero-contact drying of wafers.

[0009] 2. Technical Solution:

[0010] To solve the above problems, the present invention adopts the following technical solution.

[0011] A fully automated multi-station drying device for semiconductor wafers includes two symmetrically arranged base plates, a conveying platform is erected between the two base plates, and the surface of the conveying platform is provided with parallel guide rails.

[0012] The drying chamber is installed in the middle of the base plate, and its interior is divided into a pretreatment area, a main drying area and a cooling area by four sets of lifting isolation doors; a channel is provided at the bottom center of each lifting isolation door, and each isolation door is controlled by an independent drive motor at the top of the drying chamber; a material transfer vehicle is slidably installed on the guide rail, and a propulsion mechanism is integrated inside the conveying platform, the drive end of which extends to the outside of the base plate.

[0013] A further improvement is that: an infrared radiation heating array is arranged on the inner wall of the main drying zone, and an air-cooling channel is provided on the inner wall of the cooling zone; a control cabinet and a cooling fan are installed on the top of the drying chamber, the control cabinet is connected to the infrared radiation heating array, and the air outlet of the cooling fan is connected to the air-cooling channel of the cooling zone.

[0014] A further improvement is that the material transfer vehicle includes: a material carrying frame with four sets of guide wheels at the bottom, the guide wheels being located between guide rails; a positioning bracket symmetrically fixed to the bottom of the material carrying frame; a multi-layered support bracket assembled within the material carrying frame; and a wafer carrier that can be detachably installed on the support bracket.

[0015] A further improvement is that the propulsion mechanism includes: a transmission groove located in the middle of the conveying platform; a pulley assembly rotatably disposed in the transmission groove; a closed-loop transmission belt covering the pulley assembly; multiple push rods equidistantly fixed on the transmission belt; a drive shaft passing through the conveying platform, one end of which is connected to the pulley assembly and the other end of which is connected to a servo motor on the outside of the base plate; the push rods and the positioning bracket of the material transfer vehicle form a lateral drive cooperation.

[0016] A further improvement is that a spring cavity is opened in the side wall of the bearing bracket, and a rotating sleeve is hinged therein by a double torsion spring. The rotating sleeve is fixed to a linkage rod with a wedge-shaped locking block. When the wedge-shaped locking block is in the horizontal position, the wafer carrier is locked.

[0017] A further improvement is that the wafer carrier includes: a disk body with an annular positioning groove; conical positioning bosses distributed in a ring along the outer edge of the annular positioning groove; and an array of microholes formed at the bottom of the annular positioning groove, the array being located within the area enclosed by the conical positioning bosses; the conical positioning bosses are used to support semiconductor wafers.

[0018] 3. Beneficial effects:

[0019] Compared with the prior art, the technical solution provided by this utility model has the following advantages:

[0020] (1) Multi-station collaborative drying: The cabin is divided into a pretreatment area, a main drying area and a cooling area by four sets of lifting isolation doors. Combined with an infrared radiation heating array (150℃±5℃) and a laminar flow air cooling system, a closed-loop process chain of "waiting-constant temperature drying-gradient cooling" is realized to eliminate wafer structure stress caused by temperature change.

[0021] (2) Transmission system: The material transfer vehicle runs automatically in the drying chamber via the guide rail. The wafer carrier uses a conical positioning boss to support the wafer in the air. It is combined with the bottom micro-hole array to evenly generate heat dissipation airflow and avoid physical contact between the wafer and the carrier. The channel height at the bottom of the lifting isolation door is precisely designed to ensure that the push rod and the guide rail slide without interference.

[0022] (3) High-efficiency automated operation: The servo motor of the propulsion mechanism drives the closed-loop transmission belt, and the lateral cooperation between the push rod and the positioning bracket precisely controls the transfer of the transfer car between the three work stations; the wedge-shaped locking block of the bearing bracket realizes one-click locking of the wafer carrier through double torsion springs, and can complete the batch processing of multi-layer wafers in one go, which improves efficiency by more than 200% compared with manual operation.

[0023] It should be noted that the structures not described in this utility model are the same as or can be implemented using existing technology, and will not be elaborated here, as they do not involve the design points and improvement directions of this utility model. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0025] Figure 2 This is a schematic diagram of the structure of the drying chamber of this utility model;

[0026] Figure 3 This is a schematic diagram of the material transfer vehicle of this utility model;

[0027] Figure 4 This is a schematic diagram of the propulsion mechanism of this utility model;

[0028] Figure 5 This is a schematic diagram of the structure of the load-bearing bracket of this utility model;

[0029] Figure 6 This is a schematic diagram of the structure of the wafer carrier disk of this utility model;

[0030] Figure 7 This is a flowchart illustrating the operation of this utility model.

[0031] Explanation of the labels in the diagram:

[0032] 1. Base plate; 2. Conveying platform; 21. Guide rail;

[0033] 3. Drying chamber; 31. Pre-treatment area; 32. Main drying area; 33. Cooling area; 34. Control cabinet; 35. Cooling fan;

[0034] 4. Lifting isolation door; 41. Passageway;

[0035] 5. Material transfer vehicle; 51. Material carrying frame; 52. Guide wheels; 53. Positioning bracket;

[0036] 54. Bearing bracket; 541. Spring cavity; 542. Rotating sleeve; 543. Double torsion spring; 544. Linkage rod; 545. Wedge-shaped locking block;

[0037] 55. Wafer carrier; 551. Disk body; 552. Annular positioning groove; 553. Conical positioning boss; 554. Microvia array; 555. Semiconductor wafer;

[0038] 6. Propulsion mechanism; 61. Transmission groove; 62. Closed-loop transmission belt; 63. Push rod; 64. Servo motor. Detailed Implementation

[0039] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the utility model will be more thorough and complete.

[0040] Please see Figures 1-7 A fully automated multi-station drying device for semiconductor wafers, the main components and structural composition of which include the following:

[0041] 1. Base system installation

[0042] Two 304 stainless steel base plates are fixed to the ground in parallel, with a spacing of 1200mm;

[0043] The conveying platform 2 is connected to the base plate 1 by high-strength bolts, and the platform surface is covered with guide rails 21.

[0044] 2. Drying chamber integration

[0045] The drying chamber 3 is welded to the middle of the base plate 1, and the inner wall is covered with a PTFE anti-corrosion layer;

[0046] Four sets of lifting isolation doors 4 are arranged along the length of the cabin: 2 sets are set between the pretreatment area 31 and the main drying area 32, and 2 sets are set between the main drying area 32 and the forced cooling area 33; the channel 41 at the bottom of the isolation door 4 is higher than the thickness of the guide rail 21 and the push rod 63.

[0047] 3. Assembly of material transfer system

[0048] The spacing of push rod 63 matches the center distance of positioning bracket 53 of material transfer vehicle 5.

[0049] A fully automated multi-station drying device for semiconductor wafers, the main operating process and steps of which include the following:

[0050] Step 1: Wafer loading (room temperature environment)

[0051] The semiconductor wafer 555 is placed on the tapered positioning boss 553 of the wafer carrier 55 (with the bottom surface suspended).

[0052] When placing the tray into the support bracket 54: If the locking mechanism is activated: Press down on the tray to make the wedge-shaped locking block 545 slide in along the inclined surface. Then, after the tray body 551 is completely placed into the support bracket 54, its torsion spring 543 drives the wedge-shaped locking block 545 to horizontally lock onto the outer surface of the tray body 551 and limit it. When taking out the tray body 551: Press down directly on the wedge-shaped locking block 545 to make it rotate downward, so that the wedge-shaped locking block 545 no longer limits the tray body 551. At this time, the tray body 551 can be freely taken out from above the support bracket 54.

[0053] Step 2: Awaiting processing (Preprocessing area 31)

[0054] The material transfer vehicle (5) is pushed into the pretreatment area (31) via the guide rail (21) to wait;

[0055] Step 2.1: Initial positioning of propulsion mechanism 6

[0056] The servo motor (64) drives the transmission rod to rotate, which in turn drives the pulley group to make the closed-loop transmission belt (62) rotate synchronously until the push rod (63) is located next to the positioning bracket (53) on the left.

[0057] Step 3: Main drying (main drying zone 32)

[0058] Open the isolation door between the pretreatment zone 31 and the main drying zone 32 (4);

[0059] The servo motor (64) drives the push rod (63) to push the positioning bracket (53) and send the transfer car into the main drying area (32); the infrared radiation heating array heats up to 150±5℃; the heat can also enter the bottom of the disk body through the micro-hole array (554) at the bottom. Since the semiconductor wafer (555) is placed on the conical positioning boss (553) at this time, there is a gap between the two, so the heat can simultaneously dry the bottom, side and top of the semiconductor wafer (555).

[0060] Step 4: Gradient cooling (forced cooling zone 33)

[0061] The propulsion mechanism (6) drives the transfer vehicle 5 to the cooling zone (33) again; the cooling fan (35) inputs clean air through the laminar flow distribution channel until the semiconductor wafer (555) is slowly cooled to below 80°C.

[0062] The above-described embodiments are merely illustrative of certain implementations of this utility model, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A fully automated multi-station drying device for semiconductor wafers, comprising two symmetrically arranged base plates (1), characterized in that, A conveying platform (2) is erected between the two base plates (1), and two guide rails (21) are arranged parallel to each other on the surface of the conveying platform (2). The base plate (1) is equipped with a drying chamber (3) in the middle, which is divided into a pretreatment area (31), a main drying area (32) and a cooling area (33) by four sets of lifting isolation doors (4). The lifting isolation door (4) has a channel (41) at the bottom center, and each isolation door (4) is controlled by an independent drive motor at the top of the drying chamber (3); Material transfer vehicle (5) is slidably mounted on the guide rail (21). The conveying platform (2) has an integrated propulsion mechanism (6) inside, the drive end of which extends to the outside of the base plate (1).

2. The fully automated multi-station drying device for semiconductor wafers according to claim 1, characterized in that, The inner wall of the main drying zone (32) is provided with an infrared radiation heating array, and the inner wall of the cooling zone (33) is provided with air cooling channels. The top of the drying chamber (3) is equipped with a control cabinet (34) and a cooling fan (35). The control cabinet (34) is connected to an infrared radiation heating array, and the air outlet of the cooling fan (35) is connected to the air cooling channel of the cooling zone (33).

3. The fully automated multi-station drying device for semiconductor wafers according to claim 1, characterized in that, The material transfer vehicle (5) includes: The material carrier frame (51) is equipped with four sets of guide wheels (52) at the bottom, and the guide wheels (52) are located between the guide rails (21); Positioning brackets (53) are symmetrically fixed to the bottom of the material carrier frame (51). Multi-layered load-bearing brackets (54) are assembled within the load-bearing frame (51). A wafer carrier (55) is detachably mounted on a support bracket (54).

4. The fully automated multi-station drying device for semiconductor wafers according to claim 1, characterized in that, The propulsion mechanism (6) includes: A transmission groove (61) is located in the middle of the conveyor platform (2); Rotate the pulley assembly located in the transmission groove (61); Closed-loop drive belt (62) with covered pulley assembly; Multiple push rods (63) are fixed at equal intervals on the transmission belt (62); The drive shaft that runs through the conveyor platform (2) is connected to a pulley group at one end and to a servo motor (64) on the outside of the base plate (1) at the other end. The push rod (63) and the positioning bracket (53) of the material transfer vehicle (5) form a lateral drive cooperation.

5. The fully automated multi-station drying device for semiconductor wafers according to claim 3, characterized in that, The support bracket (54) has a spring cavity (541) on its side wall, and a rotating sleeve (542) is hinged inside by a double torsion spring (543). The rotating sleeve (542) is fixed to a linkage rod (544) with a wedge-shaped locking block (545). When the wedge-shaped locking block (545) is in the horizontal position, the wafer carrier (55) is locked.

6. The fully automated multi-station drying apparatus for semiconductor wafers according to claim 3, characterized in that, The wafer carrier (55) comprises: A disc body (551) with an annular positioning groove (552); Conical positioning bosses (553) are distributed in a ring along the outer edge of the annular positioning groove (552); A micro-hole array (554) is formed at the bottom of the annular positioning groove (552), which is located within the area enclosed by the conical positioning boss (553); The tapered positioning boss (553) is used to support the semiconductor wafer (555).

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