阅读说明：本技术 一种定位图案转移的刻蚀装置及其刻蚀方法 (Etching device for transferring positioning pattern and etching method thereof ) 是由 许红梅 闫艳琴 王迪 于 2021-09-09 设计创作，主要内容包括：本发明公开了一种定位图案转移的刻蚀装置,包括：输送装置,以及输送装置上方设置的转移组件,输送装置设置有若干凹槽,每个硅片根据光刻胶图案黏附有刻蚀腔体；每一层刻蚀腔体的截面大小由上到下依次增大,每层刻蚀腔体由环状纤维构筑而成,并通过支撑纤维连接每个环状纤维以加固；支撑纤维向刻蚀腔体内侧延伸一定长度；至少在伸长部顶端和尾端分别涂覆有超亲水介质层和超疏水介质层；转移组件包括若干精控头,精控头包括距离传感器、喷头、伸缩控制杆。该设备根据硅片表面的光刻胶图案,将刻蚀液忠诚地喷涂于刻蚀腔体内；通过精控头的精确定位,减少刻蚀液滴加错位的问题,并且精确控制液面的平整度,实现对液体厚度的精确控制。(The invention discloses an etching device for transferring positioning patterns, which comprises: the silicon wafer etching device comprises a conveying device and a transfer assembly arranged above the conveying device, wherein the conveying device is provided with a plurality of grooves, and each silicon wafer is adhered with an etching cavity according to a photoresist pattern; the cross section of each layer of etching cavity is sequentially increased from top to bottom, each layer of etching cavity is constructed by annular fibers, and each annular fiber is connected through supporting fibers for reinforcement; the supporting fiber extends a certain length towards the inner side of the etching cavity; at least the top end and the tail end of the extension part are respectively coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer; the transfer assembly comprises a plurality of precise control heads, and each precise control head comprises a distance sensor, a spray head and a telescopic control rod. The equipment sprays etching liquid into an etching cavity faithfully according to a photoresist pattern on the surface of a silicon wafer; through the accurate positioning of the accurate control head, the problem of etching liquid dropping and dislocation is reduced, the flatness of the liquid level is accurately controlled, and the accurate control of the liquid thickness is realized.)

1. An etching apparatus for localized pattern transfer, comprising: the silicon wafer transferring device comprises a conveying device and a transferring assembly arranged above the conveying device, and is characterized in that a plurality of grooves for mounting silicon wafers are equidistantly arranged on the upper surface of the conveying device, and each silicon wafer is adhered with an etching cavity according to a photoresist pattern;

the etching cavity is at least two layers, the height of each layer of the etching cavity is determined according to the preset amount of etching solution, the section size of each layer of the etching cavity is sequentially increased from top to bottom, each layer of the etching cavity is constructed by overlapping a plurality of annular fibers which are connected end to end, and each annular fiber is connected through a supporting fiber for reinforcement; the supporting fiber extends to the inner side of the etching cavity for a certain length; at least the top end and the tail end of the extension part are respectively coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer;

the transfer assembly comprises a plurality of precision control heads, each precision control head comprises a plurality of distance sensors, a plurality of spray heads and a plurality of telescopic control rods, the distance sensors are used for ensuring that the centers of the precision control heads are superposed with the center of the etching cavity, and each spray head corresponds to different solutions or solutions with different concentrations; the telescopic control rod is used for controlling an included angle between the extension part and the top surface of the etching cavity.

2. The etching apparatus for positioning pattern transfer according to claim 1, wherein: the distance sensors are distributed on the outer edge of the spray head in an equal angle mode and are arranged on a bisector of the horizontal and vertical fine control heads.

3. The etching apparatus for positioning pattern transfer according to claim 1, wherein: the spray heads are arranged in a regular triangle structure, the spray heads can be automatically switched to the center of the precision control head to realize blanking, and the blanking is recovered.

4. The etching apparatus for positioning pattern transfer according to claim 1, wherein: and the fine control head is also provided with moisture absorption fibers for absorbing moisture and etching liquid, and the moisture absorption fibers for absorbing the moisture are profiled fibers or hollow fibers.

5. The etching apparatus for positioning pattern transfer according to claim 4, wherein: the moisture absorption fiber is of a hollow structure with a C-shaped, M-shaped, triangle-like and star-shaped cross section.

6. The etching apparatus for positioning pattern transfer according to claim 1, wherein: the upper part of the groove of the conveying device is provided with a plurality of precision control heads in an array mode, and the working state of the precision control heads is determined according to the arrangement of the etching cavities.

7. The etching apparatus for positioning pattern transfer according to claim 1, wherein: the annular fibers are coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer at intervals from top to bottom, and the annular fibers at the top layer are coated with the super-hydrophobic medium layer.

8. The etching apparatus for positioning pattern transfer according to claim 7, wherein: the super-hydrophilic medium layer is coated on the surfaces of the annular fibers of the top layer, and the liquid drops can form adsorption force with the surfaces of the annular fibers of the top layer, so that the contact surface of liquid and the annular fibers is always higher than the middle liquid level, and an inwards concave liquid level with a low middle part and a high periphery is formed.

9. An etching method based on the etching device for transferring the positioning pattern as claimed in claims 1 to 8, characterized by comprising the steps of:

s1, the conveying device moves to drive the silicon wafers in the grooves to move, and the conveying device moves to the position below the transfer assembly and stops;

s2, the precision control head rotates along a cross-shaped preset track, and the position where the center of the precision control head is overlapped with the center of the etching cavity is found;

s3, one of the nozzles automatically switches to the center and drips a certain amount of etching liquid to the etching cavity according to a preset amount, and the liquid surface forms an indent with a low middle part and a high periphery due to surface tension;

s4, accurately controlling the included angle between the corresponding extension part and the top layer of the annular fiber through each telescopic control rod on the fine control head, wherein the super-hydrophilic medium layer at the top end part of the extension part forms affinity to the inner concave surface of the center of liquid, the super-hydrophobic medium layer at the tail end part of the extension part forms repulsion to the peripheral surface of the liquid, the super-hydrophilic medium layer and the super-hydrophobic medium layer act to compensate the empty groove of the inner concave center and level the liquid level, and the hygroscopic fiber is used for absorbing moisture to ensure that the height of the leveled liquid is consistent with the height of each layer of etching cavity;

and S5, after the spray heads are restored, other spray heads automatically switch to the center to drop a certain amount of etching liquid into the etching cavity according to a preset amount, and the operations of S3 and S4 are repeated, so that the etching liquid and the surface of the silicon wafer are subjected to etching reaction.

10. The etching method of the etching device for transferring the positioning pattern according to claim 9, wherein: in S2, in the predetermined cross-shaped track, the distance sensor detects the connecting line between the center of the fine control head and the center of the etching chamber, and the position with the shortest distance is the center coincidence.

Technical Field

The invention relates to the technical field of accurate positioning or pattern transfer, in particular to an etching device for positioning pattern transfer and an etching method thereof.

Background

The pattern transfer technique is a process for transferring the patterns to be left to other materials with loyalty, and this step plays a significant role in the manufacturing process of semiconductor integrated circuits. During the fabrication of silicon wafers, unwanted material is removed from the wafer surface by etching. The most common etching method is wet etching, which is a technique for removing a part to be etched by utilizing a chemical reaction between a solution and a film to form a micro-nano pattern structure on various functional materials.

The existing etching equipment can not accurately control the etching liquid dripped on each silicon chip, has insufficient positioning precision during etching, is easy to cause phenomena such as dripping dislocation of the etching liquid and the like, and can not carry out large-scale etching production and processing.

In view of the above, there is a need to improve etching equipment in the prior art to solve the problems of difficulty in controlling the etching depth of the silicon wafer, poor etching liquid dropping and dislocation, and low etching production and processing efficiency.

Disclosure of Invention

The invention overcomes the defects of the prior art and provides an etching device for transferring positioning patterns and an etching method thereof.

In order to achieve the purpose, the invention adopts the technical scheme that: an etching apparatus for localized pattern transfer, comprising: the silicon wafer transferring device comprises a conveying device and a transferring assembly arranged above the conveying device, and is characterized in that a plurality of grooves for mounting silicon wafers are equidistantly arranged on the upper surface of the conveying device, and each silicon wafer is adhered with an etching cavity according to a photoresist pattern;

the etching cavity is at least two layers, the height of each layer of the etching cavity is determined according to the preset amount of etching solution, the section size of each layer of the etching cavity is sequentially increased from top to bottom, each layer of the etching cavity is constructed by overlapping a plurality of annular fibers which are connected end to end, and each annular fiber is connected through a supporting fiber for reinforcement; the supporting fiber extends to the inner side of the etching cavity for a certain length; at least the top end and the tail end of the extension part are respectively coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer;

the transfer assembly comprises a plurality of precision control heads, each precision control head comprises a plurality of distance sensors, a plurality of spray heads and a plurality of telescopic control rods, the distance sensors are used for ensuring that the centers of the precision control heads are superposed with the center of the etching cavity, and each spray head corresponds to different solutions or solutions with different concentrations; the telescopic control rod is used for controlling an included angle between the extension part and the top surface of the etching cavity.

In a preferred embodiment of the invention, the distance sensors are distributed on the outer edge of the spray head in an equal angle mode and are arranged on a horizontal bisector and a vertical bisector of the fine control head.

In a preferred embodiment of the invention, the spray heads are arranged in a regular triangle structure, and the spray heads can be automatically switched to the center of the precision control head to realize blanking and then reset after blanking.

In a preferred embodiment of the invention, the fine control head is further provided with moisture absorption fibers for absorbing moisture and etching liquid, and the moisture absorption fibers for absorbing moisture and etching liquid are profiled fibers or hollow fibers.

In a preferred embodiment of the present invention, the absorbent fibers have a cross-sectional C-shape, a cross-sectional m-shape, a cross-sectional triangular shape, a cross-sectional star shape, or a hollow structure.

In a preferred embodiment of the present invention, a plurality of the fine control heads are arrayed above the groove of the conveying device, and the working state of the fine control heads is determined according to the arrangement of the etching cavities.

In a preferred embodiment of the invention, the ring-shaped fibers are coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer at intervals from top to bottom, and the ring-shaped fibers at the top layer are coated with the super-hydrophobic medium layer.

In a preferred embodiment of the invention, the surface of the annular fiber of the top layer is coated with a super-hydrophilic medium layer, and the liquid drops can form adsorption force with the surface of the annular fiber of the top layer, so that the contact surface of the liquid and the annular fiber is always higher than the middle liquid level, and an inner concave liquid level with a low middle part and a high periphery is formed.

The invention also provides an etching method of the etching device for transferring the positioning pattern, which is characterized by comprising the following steps of:

s1, the conveying device moves to drive the silicon wafers in the grooves to move, and the conveying device moves to the position below the transfer assembly and stops;

s2, the precision control head rotates along a cross-shaped preset track, and the position where the center of the precision control head is overlapped with the center of the etching cavity is found;

s3, one of the nozzles automatically switches to the center and drips a certain amount of etching liquid to the etching cavity according to a preset amount, and the liquid surface forms an indent with a low middle part and a high periphery due to surface tension;

s4, accurately controlling the included angle between the corresponding extension part and the top layer of the annular fiber through each telescopic control rod on the fine control head, wherein the super-hydrophilic medium layer at the top end part of the extension part forms affinity to the inner concave surface of the center of liquid, the super-hydrophobic medium layer at the tail end part of the extension part forms repulsion to the peripheral surface of the liquid, the super-hydrophilic medium layer and the super-hydrophobic medium layer act to compensate the empty groove of the inner concave center and level the liquid level, and the hygroscopic fiber is used for absorbing moisture to ensure that the height of the leveled liquid is consistent with the height of each layer of etching cavity;

and S5, after the spray heads are restored, other spray heads automatically switch to the center to drop a certain amount of etching liquid into the etching cavity according to a preset amount, and the operations of S3 and S4 are repeated, so that the etching liquid and the surface of the silicon wafer are subjected to etching reaction.

In a preferred embodiment of the present invention, in S2, within the predetermined cross-shaped track, the distance sensor detects that the center of the fine control head and the central connecting line of the etching chamber are at the position with the shortest distance, i.e. the positions are coincident with each other.

The invention solves the defects in the background technology, and has the following beneficial effects:

(1) the invention provides etching equipment based on a pattern transfer technology, which can be used for spraying etching liquid into an etching cavity faithfully according to a photoresist pattern on the surface of a silicon wafer; through the accurate positioning of the accurate control head, the problem of the adding dislocation of the etching liquid is reduced, the flatness of the liquid level is accurately controlled, the accurate control of the liquid thickness is realized, and the etching depth is ensured to be within a preset range.

(2) The precision control head used by the invention rotates along a cross-shaped preset track, the distance sensor detects the center of the precision control head and the center of the etching cavity to find the shortest distance, so that the position of the spray center of the spray head is superposed with the center of the etching cavity, and the positioning accuracy of the device is improved.

(3) The annular fiber is coated with the super-hydrophilic medium layer and the super-hydrophobic medium layer at intervals from top to bottom, and the structure is favorable for constructing a surrounding space with alternate hydrophilic and hydrophobic properties and constructing a more three-dimensional liquid column structure. Although the structure forms concave-convex on the side surface of the liquid column, a hydrophilic-hydrophobic arrangement mode is adopted, the convex surface can be compensated by the concave surface, errors caused by the concave-convex surface can be completely ignored, and the errors can be completely ignored during thickness calculation.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts;

FIG. 1 is a perspective block diagram of a preferred embodiment of the present invention;

FIG. 2 is a perspective view of an etch chamber according to a preferred embodiment of the present invention;

FIG. 3 is a perspective view of the fine control head of the preferred embodiment of the present invention;

in the figure: 1. a conveying device; 2. a silicon wafer; 3. etching the cavity; 31. a cyclic fiber; 32. a support fiber; 33. an extension portion;

4. a transfer assembly; 41. a fine control head; 411. a distance sensor; 412. a spray head; 413. a telescopic control rod; 414. a moisture-absorbing fiber.

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.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be considered limiting of the scope of the present application. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the invention, the meaning of "a plurality" is two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art through specific situations.

As shown in fig. 1, a perspective view of an etching apparatus for positioning pattern transfer is shown. The etching equipment can spray etching liquid into the etching cavity 3 faithfully according to the photoresist pattern on the surface of the silicon wafer 2; through the accurate positioning of the precise control head 41, the problem of the adding dislocation of the etching liquid is reduced, the flatness of the liquid level is accurately controlled, the accurate control of the liquid thickness is realized, and the etching depth is ensured to be within a preset range.

The etching equipment comprises: the silicon wafer etching device is characterized in that a plurality of grooves for mounting silicon wafers 2 are equidistantly arranged on the upper surface of the conveying device 1, and each silicon wafer 2 is adhered with an etching cavity 3 according to a photoresist pattern. A plurality of fine control heads 41 are arrayed above the groove of the conveying device 1, and the working state of the fine control heads 41 is determined according to the arrangement of the etching cavities 3.

As shown in fig. 2, the etching chamber 3 has at least two layers, the height of each layer of the etching chamber 3 is determined according to the predetermined amount of the etching solution, the cross-sectional size of each layer of the etching chamber 3 is sequentially increased from top to bottom, each layer of the etching chamber 3 is constructed by overlapping a plurality of annular fibers 31 connected end to end, and each annular fiber 31 is connected through a support fiber 32 for reinforcement; the supporting fiber 32 extends a certain length towards the inner side of the etching cavity 3; at least the top end and the tail end of the extension part 33 are respectively coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer.

The ring-shaped fibers 31 are coated with a super-hydrophilic medium layer and a super-hydrophobic medium layer at intervals from top to bottom, and the top ring-shaped fibers 31 are coated with the super-hydrophobic medium layer. The super-hydrophilic medium layer is coated on the surface of the annular fiber 31 of the top layer, and the liquid drops can form adsorption force with the surface of the annular fiber 31 of the top layer, so that the contact surface of the liquid and the annular fiber 31 is always higher than the middle liquid level, and an inner concave liquid level with a low middle part and a high periphery is formed.

According to the invention, the annular fiber 31 is coated with the super-hydrophilic medium layer and the super-hydrophobic medium layer at intervals from top to bottom, and the structure is favorable for constructing a surrounding space with alternate hydrophilic and hydrophobic properties and is favorable for constructing a more three-dimensional liquid column structure. Although the structure forms concave-convex on the side surface of the liquid column, a hydrophilic-hydrophobic arrangement mode is adopted, the convex surface can be compensated by the concave surface, errors caused by the concave-convex surface can be completely ignored, and the errors can be completely ignored during thickness calculation.

The supporting fiber 32 is made of high-strength fiber materials, preferably aramid fiber 1414, the fiber is high in strength and stable in chemical performance, and is suitable for serving as a support of the etching cavity 3, and when liquid is dripped into the surrounding space of the etching cavity 3, the etching cavity 3 is guaranteed not to deform.

The etching chamber 3 of the present invention may be dropped with corrosive liquids, such as formic acid, acetic acid, and the like. The polyphenylene sulfide fiber is adopted as the annular fiber 31 laminated in the etching cavity 3, so that the chemical resistance and the heat stability of the etching cavity 3 are ensured to be good. Even if the strength of the fiber is not changed for one week under the boiling point, formic acid and acetic acid with the temperature of 93 ℃ have no influence, and the fiber can be strongly degraded only under the condition of a strong oxidant, namely the etching cavity 3 can detect the liquid thickness of any solution except the strong oxidant with certain temperature and certain concentration.

The invention adds liquid drops into the enclosed space of the etching cavity 3, is not limited to the use of devices such as a burette, a quantitative liquid adding device, a digital automatic burette and the like which are manually titrated, and aims to accurately control the quantity and the volume of the liquid drops added into the etching cavity 3 in a certain way. The drops can be accurately, automatically and reliably dripped by utilizing potentiometric titration, photometric titration, polarographic titration, conductometric titration, temperature titration and the like.

As shown in fig. 3, the transferring assembly 4 includes a plurality of precision control heads 41, each precision control head 41 includes a plurality of distance sensors 411, a plurality of nozzles 412, and a plurality of telescopic control rods 413, the distance sensors 411 are used to ensure that the centers of the precision control heads 41 and the etching chamber 3 coincide, and each nozzle 412 corresponds to different solutions or solutions with different concentrations.

The included angle between the corresponding extension part 33 and the top layer of the annular fiber 31 is accurately controlled through each telescopic control rod 413 on the fine control head 41, the super-hydrophilic medium layer at the top end part of the extension part 33 forms affinity to the inner concave surface of the center of liquid, the super-hydrophobic medium layer at the tail end part of the extension part 33 forms repulsion force to the peripheral surface of the liquid, the super-hydrophilic medium layer and the super-hydrophobic medium layer compensate the empty groove of the inner concave center and level the liquid surface under the action of the super-hydrophilic medium layer and the liquid surface, and the moisture absorption fiber 414 absorbs moisture to ensure that the height of the leveled liquid is consistent with the height of each layer of etching cavity 3.

The nozzles 412 are arranged in a regular triangle structure, and the nozzles 412 can be automatically switched to the center of the fine control head 41 to realize blanking and then reset. The distance sensors 411 are equiangularly distributed on the outer edge of the head 412 and are arranged on the bisectors of the fine control head 41 in the horizontal and vertical directions. The fine control head 41 rotates along a cross-shaped preset track to find the position where the center of the fine control head 41 is overlapped with the center of the etching cavity 3. The precision control head 41 used in the invention rotates along a cross-shaped preset track, the distance sensor 411 detects the center of the precision control head 41 and the center of the etching cavity 3 to find the shortest distance, so that the position of the spraying center of the spray head 412 is superposed with the center of the etching cavity 3, and the positioning accuracy of the device is improved.

The fine control head 41 is also provided with moisture absorption fibers 414 for absorbing moisture and etching liquid, and the moisture absorption fibers 414 for absorbing moisture and etching liquid are profiled fibers or hollow fibers. The absorbent fibers 414 are of C-shaped, M-shaped, triangular, star-shaped, hollow cross-section.

The invention also provides an etching method of the etching device for transferring the positioning pattern, which is characterized by comprising the following steps of:

s1, the conveying device 1 moves to drive the silicon wafer 2 in the groove to move, and the conveying device 1 moves to the position below the transfer component 4 and stops;

s2, the fine control head 41 rotates along a cross-shaped preset track, and the position where the center of the fine control head 41 is overlapped with the center of the etching cavity 3 is found;

s3, one of the nozzles 412 automatically switches to the center and drops a certain amount of etching liquid to the etching cavity 3 according to a preset amount, and the liquid surface forms an inward concave with a low middle part and a high periphery due to surface tension;

s4, accurately controlling the included angle between the corresponding extension part 33 and the top layer of the annular fiber 31 through each telescopic control rod 413 on the fine control head 41, wherein the super-hydrophilic medium layer at the top end part of the extension part 33 forms affinity to the inner concave surface of the liquid center, the super-hydrophobic medium layer at the tail end part of the extension part 33 forms repulsion force to the peripheral surface of the liquid, the two functions realize compensation of the empty groove and the leveling liquid level of the inner concave center, and the moisture absorption fiber 414 absorbs the liquid to ensure that the height after leveling is consistent with the height of each layer of etching cavity 3;

s5, after the shower nozzle 412 is restored, other shower nozzles 412 automatically switch to the center to drop a certain amount of etching liquid to the etching cavity 3 according to a preset amount, and the operations of S3 and S4 are repeated, so that the etching liquid and the surface of the silicon wafer 2 are subjected to etching reaction.

It should be noted that in S2, within the predetermined cross-shaped track, the distance sensor 411 detects the connection line between the center of the fine control head 41 and the center of the etching chamber 3, which is the position with the shortest distance, i.e. the center is coincident.

In light of the foregoing description of the preferred embodiment of the present invention, it is to be understood that various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.