CN110976377B

CN110976377B - Ultrasonic cleaning device for wafer cleaning

Info

Publication number: CN110976377B
Application number: CN201911256467.1A
Authority: CN
Inventors: 谢广钦
Original assignee: Actfive Shanghai Washing Machine Co ltd
Current assignee: Actfive Shanghai Washing Machine Co ltd
Priority date: 2019-12-10
Filing date: 2019-12-10
Publication date: 2022-08-19
Anticipated expiration: 2039-12-10
Also published as: CN110976377A

Abstract

The invention relates to the technical field of integrated circuits and discloses an ultrasonic cleaning device for wafer cleaning. This an ultrasonic cleaning device for wafer cleaning, servo structure's translation rate is along with the center that is close to the mobile station accelerates gradually, reduce with the dotted line speed that is close to central point and offset, make every point receive ultrasonic energy and keep even, the supersound area of this application is threadiness simultaneously, servo structure translation rate and the rotational speed of mobile station are to the cooperation, once can wash the surface of whole wafer completely, because the wafer eccentric rotation, the rotation state that can calculate the wafer through the time of wafer space process position inductor, be convenient for simultaneously mark the position of wafer, therefore both can make the washing route at every turn the same, guarantee the identity of clearance, also can design initial position in a flexible way and wash the route.

Description

Ultrasonic cleaning device for wafer cleaning

Technical Field

The invention relates to the technical field of integrated circuits, in particular to an ultrasonic cleaning device for wafer cleaning.

Background

With the improvement of single wafer process, the requirement for cleaning technology is higher and higher, and the single wafer cleaning technology is favored by many wafer foundries and large scale integrated circuit manufacturing enterprises, please refer to fig. 5, wherein while the wafer rotates at a constant speed, the ultrasonic generator sweeps back from the edge to the center of the wafer until the entire wafer surface is cleaned.

On one hand, due to the difference of the radius, the speed of the points on different circumferences on the wafer is different, the speed is slower when the points are closer to the center, and on the contrary, the closer to the center, the received sound wave energy density is stronger, the cleaning strength of the edge position is insufficient, the actual requirement is difficult to meet, and the center position is damaged due to the over-strong energy.

Secondly, the silicon wafer cleaning is usually performed in a closed chamber and immersed in the cleaning solution, so that the rotation state of the wafer is not convenient to observe, and when the wafer rotates abnormally, the ultrasonic energy may damage the wafer.

Disclosure of Invention

Aiming at the defects of the background technology, the invention provides the technical scheme of the ultrasonic cleaning device for cleaning the wafer, which has the advantages of simple structure, uniform sweeping and timely feedback, and solves the problems in the background technology.

The invention provides the following technical scheme: the utility model provides a be used for abluent supersound belt cleaning device of wafer, is including wasing chamber, drive structure, shifting boom, the output of drive structure runs through and washs chamber and swinging boom fixed connection, the eccentric mobile station that is provided with on the swinging boom, one side fixed mounting of swinging boom has the position sensor, the servo structure of horizontal migration is installed to the shifting boom, the speed of servo structure is along with the center uniform velocity increase that is close the moving station, the ultrasonic emergence structure that sound energy is linear irradiation is installed to the lower extreme of servo structure.

Preferably, the mobile station is movably connected with the rotating arm, a sliding rail for moving the mobile station is arranged on the rotating arm, the starting point of the sliding rail for the rotating arm is the center of the rotating arm, and the end point and the starting point of the sliding rail for the rotating arm are provided with electromagnetically controlled locking structures.

Preferably, the moving arm is provided with at least two position mark structures of the servo structure, and the moving end point of the servo structure is collinear with the mobile station.

Preferably, the ultrasonic generating structure comprises three sharp-mouth-shaped ultrasonic nozzles arranged side by side, the middle nozzle is kept vertical, the lower ends of the nozzles at the two sides are inclined beyond the middle part, and the energy intensity of the ultrasonic nozzles at the middle part of the ultrasonic generating structure is smaller than that at the two sides.

Preferably, when the servo structure moves to the end position, the extreme edge of the irradiation line segment of the ultrasonic generating structure just reaches the center of the mobile station, and only the spray head of the ultrasonic generating structure closest to the center is turned on at the moment, and then the spray heads of other ultrasonic generating structures are turned on after the turning is finished.

Preferably, when the servo structure moves to the initial position, the ultrasonic generating structure is closed, and when the wafer edge gap is maximum, the servo structure starts to turn and simultaneously opens the ultrasonic generating structure.

The invention has the following beneficial effects:

1. this an ultrasonic cleaning device for wafer cleaning, on the one hand, servo structure's translation rate is accelerated gradually along with the center that is close to the mobile station, reduces with the dotted line speed that is close to central point and offsets, makes every point accept ultrasonic energy and keeps even, and on the other hand, the washing area of current supersound shower nozzle of comparison is the dot, and the supersound area of this application is threadiness, and servo structure translation rate and the rotational speed of mobile station are to the cooperation, once can wash the surface of whole wafer completely, and abluent more even.

2. This an ultrasonic cleaning device for wafer cleaning, because the wafer eccentric rotation, the rotation state that can calculate the wafer through the time of wafer space through position inductor in time discovers the wafer rotation anomaly, in time gets rid of the problem, is convenient for carry out the sign to the position of wafer simultaneously, therefore both can make the washing route at every turn the same, guarantees the identity of clearance, also can design initial position and washing route in a flexible way, makes the washing more scientific.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of the movement path and the ultrasonic cleaning path of a wafer according to the present invention;

FIG. 3 is a schematic view of an irradiation region of an ultrasound generating structure of the present invention;

FIG. 4 is a control schematic of the present invention;

fig. 5 is a schematic diagram of a conventional single wafer ultrasonic cleaning structure.

In the figure: 1. a cleaning chamber; 2. a drive structure; 3. a moving arm; 4. a mobile station; 5. a servo structure; 6. an ultrasound generating structure; 7. a position sensor; 8. a rotating arm; 9. and (5) a wafer.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, an ultrasonic cleaning apparatus for cleaning a wafer includes a cleaning chamber 1, a driving structure 2, and a moving arm 3, wherein an output end of the driving structure 2 penetrates through the cleaning chamber 1 and is fixedly connected to a rotating arm 8, the rotating arm 8 is eccentrically provided with a moving platform 4, the moving platform 4 fixes the wafer 9 through a suction cup during cleaning, the rotating arm 8 drives the wafer 9 to eccentrically rotate when rotating, a rotation track of the wafer 9 is as shown in fig. 2, one side of the rotating arm 8 is fixedly provided with a position sensor 7, because the wafer 9 eccentrically rotates, the wafer 9 intermittently passes over the position sensor 7, the position sensor 7 transmits passing information of the wafer 9 to a control host, and further identifies a rotation state of the wafer 9, the moving arm 3 is provided with a horizontally moving servo structure 5, a speed of the servo structure 5 increases at a constant speed as approaching to a center of the moving platform 4, the ultrasonic wave generator is matched with the speed reduction of the points on the wafer 9 to ensure that the sound wave energy received by each point on the wafer 9 is consistent, and the ultrasonic wave generator 6 with linear irradiation of the sound wave energy is arranged at the lower end of the servo structure 5 to ensure that the irradiation completely covers the surface of the wafer 9.

The movable table 4 is movably connected with the rotating arm 8, a sliding rail for the movable table 4 to move is arranged on the rotating arm 8, the starting point of the sliding rail of the rotating arm 8 is the center of the rotating arm 8, electromagnetic control locking structures are arranged at the end point and the starting point of the sliding rail of the rotating arm 8, and the locking structures are the existing mature technologies, so that description is not provided, when the movable table 4 is located at the starting point of the sliding rail, the movable table 4 and the rotating arm 8 are coaxial, the wafer 9 rotates at a constant speed, and when the movable table 4 is located at the end point of the sliding rail, the wafer 9 rotates eccentrically.

The moving arm 3 is provided with at least two position marking structures of the servo structure 5, the moving end point of the servo structure 5 is collinear with the moving platform 4, the marking structures can be pressure sensors, proximity switches or photoelectric sensors arranged at the moving start point and the moving end point of the servo structure 5, the photoelectric sensors are arranged in the embodiment, information is transmitted between the photoelectric sensors and the control host, the moving state of the servo structure 5 is calculated by moving the servo structure 5 to the end point position and the starting position, and then the moving parameters of the servo structure 5 are detected and corrected.

Wherein, supersound emergence structure 6 is the sharp mouth shape supersound shower nozzle that three set up side by side, and the maintenance of middle part shower nozzle is perpendicular, the super middle part slope of both sides shower nozzle lower extreme, the middle part supersound shower nozzle energy intensity of supersound emergence structure 6 is less than the intensity of both sides, the energy of shining of final three shower nozzle is the same, finally as shown in figure 3 to the ultrasonic effect of wafer 9, compare and reform transform the shower nozzle, this kind of mode cost is less, and when the slope extends irradiation length, three shower nozzle self erection space is great, design and installation are more nimble.

When the servo structure 5 moves to the end position, the extreme edge of the irradiation line segment of the ultrasonic generation structure 6 just reaches the center of the mobile station 4, only the spray head closest to the center is started at the moment, and other spray heads are started after the steering is finished.

Wherein, when servo structure 5 moved to the initial position, closed supersound and taken place structure 6, when 9 marginal gaps of wafer were the biggest, servo structure 5 started to turn to and opened supersound simultaneously and taken place structure 6, guaranteed the edge and wash the even of intensity, swept the same position at every turn simultaneously, guaranteed the homogeneity and the uniformity of clearance.

The working principle of the invention is as follows:

installing a wafer 9 on a mobile platform 4, ensuring the alignment of the mobile platform 4 and the wafer 9, moving the mobile platform 4 to an eccentric position, setting parameters through a control host, starting a position sensor 7 and a servo structure 5, detecting the time when a gap passes through the edge of the wafer 9 by the servo structure 5, calculating the running state of the wafer 9 by the control host, controlling the servo structure 5 to start moving when the edge space of the wafer 9 is the largest, simultaneously starting an ultrasonic generating structure 6, matching the moving speed of the servo structure 5 with the rotating speed of the wafer 9 to enable the servo structure to completely cover the surface of the whole wafer 9 at one time, cleaning the surface of the wafer 9, closing two ultrasonic nozzles far away from the center by the ultrasonic generating structure 6 when moving to the central position of the mobile platform 4, starting steering acceleration by the servo structure 5, starting all the ultrasonic nozzles after the servo structure 5 turns, and starting to move from the center to the edge, and repeating for multiple times to finish the cleaning process.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. An ultrasonic cleaning device for wafer cleaning comprises a cleaning cavity (1), a driving structure (2) and a moving arm (3), and is characterized in that: the ultrasonic cleaning device is characterized in that the output end of the driving structure (2) penetrates through the cleaning cavity (1) and is fixedly connected with a rotating arm (8), a moving platform (4) is eccentrically arranged on the rotating arm (8), a position sensor (7) is fixedly arranged on one side of the rotating arm (8), a servo structure (5) which horizontally moves is arranged on the moving arm (3), the speed of the servo structure (5) is increased at a constant speed along with the approach of the center of the moving platform (4), and an ultrasonic generating structure (6) with linear irradiation of sound wave energy is arranged at the lower end of the servo structure (5);

the mobile station (4) is movably connected with a rotating arm (8), a sliding rail for moving the mobile station (4) is arranged on the rotating arm (8), the starting point of the sliding rail of the rotating arm (8) is the center of the rotating arm (8), and an electromagnetic control locking structure is arranged at the end point and the starting point of the sliding rail of the rotating arm (8);

the mobile arm (3) is provided with position marking structures of at least two servo structures (5), and the mobile terminal points of the servo structures (5) are collinear with the mobile station (4);

the ultrasonic generating structure (6) is composed of three sharp-mouth-shaped ultrasonic nozzles arranged side by side, the nozzle at the middle part is kept vertical, the lower ends of the nozzles at two sides are inclined towards the middle part, and the energy intensity of the ultrasonic nozzle at the middle part of the ultrasonic generating structure (6) is smaller than that of the ultrasonic nozzles at two sides;

when the servo structure (5) moves to the end position, the extreme edge of the irradiation line segment of the ultrasonic generating structure (6) just reaches the center of the mobile station (4), and only the spray head of the ultrasonic generating structure (6) closest to the center is started at the moment, and the spray heads of other ultrasonic generating structures (6) are started after the steering is finished;

when the servo structure (5) moves to the initial position, the ultrasonic generating structure (6) is closed, and when the gap of the edge of the wafer is the largest, the servo structure (5) starts to turn and simultaneously opens the ultrasonic generating structure (6);

installing a wafer (9) on a mobile platform (4), ensuring the alignment of the mobile platform (4) and the wafer (9), moving the mobile platform (4) to an eccentric position, setting parameters through a control host, starting a position sensor (7) and a servo structure (5), detecting the time when an edge gap of the wafer (9) passes by the servo structure (5), calculating the running state of the wafer (9) by the control host, controlling the servo structure (5) to start moving when the edge space of the wafer (9) is maximum, simultaneously starting an ultrasonic generating structure (6), matching the moving speed of the servo structure (5) with the rotating speed of the wafer (9) to ensure that the servo structure can completely cover the surface of the whole wafer (9) at one time, cleaning the surface of the wafer (9), and closing two ultrasonic nozzles far away from the center by the ultrasonic generating structure (6) when the wafer (9) moves to the central position of the mobile platform (4), meanwhile, the servo structure (5) starts to turn to accelerate, all the ultrasonic spray heads are started after the servo structure (5) turns to finish, the ultrasonic spray heads start to move from the center to the edge, and the cleaning process is finished after the ultrasonic spray heads are repeated for multiple times.