CN219916172U - Mask assembly - Google Patents

Abstract

The utility model provides a mask assembly, which relates to the field of semiconductor photoetching and comprises a lower mask, wherein the lower mask comprises a lower mask body and a positioning device, the lower mask body is provided with a first surface, the positioning device is provided with at least three positioning parts, each positioning part is arranged on the first surface, a plurality of positioning parts are distributed around a first axis vertical to the first surface, a chip substrate is arranged on the first surface in an area surrounded by the positioning parts, the outer side wall of the positioning part is contacted with the outer side wall of the chip substrate, the connection line of the projection of the outer side wall of the positioning part and the contact area of the outer side wall of the chip substrate on the first surface and the projection of the first axis on the first surface is a first line segment, the included angle between two adjacent first line segments is smaller than 180 degrees, and the plurality of positioning parts can limit the movement of the chip substrate along the first surface. The mask assembly can improve the working efficiency.

Description

Mask assembly

Technical Field

The utility model relates to the technical field of semiconductor lithography, in particular to a mask assembly and an exposure machine.

Background

The photoetching process is to transfer the pattern on the mask onto chip base material, such as silicon chip, ceramic block, etc. via exposure, development, etc. with photoresist, to make the chip base material possess the photoresist pattern shape of the device to be produced, and to transfer the pattern structure onto the chip base material via chemical or physical process. Among them, alignment between reticle patterns and chip patterns is a very important factor affecting lithography accuracy.

The Chinese patent CN93105471.0 provides a double-sided register exposure machine, wherein when the double-sided register exposure machine works, firstly, two mask medicine surfaces with mirror symmetry (patterns or specific marks) are oppositely arranged, an upper mask is placed above a lower mask, the lower mask is placed on a lower mask sucker, and a lower mask vacuum channel is connected to adsorb the lower mask; the upper mask plate is sucked up by the falling upper plate sucking disc, and the distance between the two plates is limited by the fact that no medicine film friction is generated. And moving or rotating the lower mask under the microscope to completely coincide with the mask alignment mark of the upper mask. Both can then no longer have micro-movements in the horizontal plane. Lifting the upper plate sucker, sending the silicon wafer between the two plates through the silicon wafer sucker, and then falling down the upper plate sucker to enable the upper mask plate to lightly contact with the silicon wafer, and moving (along the lower surface of the upper mask plate) and rotating the silicon wafer to enable the silicon wafer to be aligned with the pattern of the upper mask plate. Sucking the silicon wafer under the upper mask plate through the air holes of the upper mask plate, deflating the air channel of the silicon wafer sucker, lifting the upper mask plate at the moment, and lifting the silicon wafer along with the upper mask plate; and withdrawing the silicon wafer sucker, and falling the upper plate sucker until the lower surface of the silicon wafer contacts the lower mask plate, so that the alignment of the upper mask plate, the lower mask plate and the silicon wafer is realized. In the prior art, a positioning device capable of positioning a silicon wafer is lacking in a lower mask plate of a double-sided mask plate exposure machine, so that the position deviation is large after the silicon wafer is placed on the lower mask plate, and the full view of the silicon wafer is required to be observed by a microscope, and the silicon wafer is horizontally moved and rotated along the axis of the silicon wafer so as to well finish the alignment of the silicon wafer and the lower mask plate. Because the existing exposure machine (photoetching machine) has limited visual field of a microscope, the alignment of a silicon wafer and a mask plate needs longer time, the efficiency is lower, and the alignment requirement of a chip substrate cannot be well met.

Disclosure of Invention

The utility model aims to provide a mask assembly, which solves the problems in the prior art, reduces the requirement on the field of view of a microscope, reduces the workload and the adjustment difficulty, and is beneficial to improving the working efficiency.

In order to achieve the above object, the present utility model provides the following solutions:

the utility model provides a mask assembly, which comprises a lower mask, wherein the lower mask comprises a lower mask body and a positioning device, the lower mask body is provided with a first surface, the positioning device is provided with at least three positioning parts, each positioning part is fixed on the first surface, each positioning part is arranged at one end of the first surface far away from the lower mask body, a plurality of positioning parts are distributed around a first axis vertical to the first surface, a chip substrate is used for being placed on part of the first surface in a region surrounded by the positioning parts, the outer side wall of each positioning part is used for being in contact with the outer side wall of the chip substrate, the connecting line of the projection of the outer side wall of each positioning part and the projection of the outer side wall of the chip substrate on the first surface is a first line segment, the included angle between any two adjacent first line segments is smaller than 180 degrees, and the plurality of positioning parts can limit the movement of the chip substrate along the first surface.

Preferably, each positioning device comprises at least three positioning pieces, a plurality of positioning pieces are distributed around the first axis, each positioning piece comprises a positioning part and a connecting part, one end of each connecting part is fixedly connected with each positioning part, the other end of each connecting part is arranged on the lower mask body, and the outer diameter of each positioning part is larger than the outer diameter of each connecting part.

Preferably, the lower mask body is provided with at least three positioning holes, each connecting portion is used for extending into each positioning hole, the outer wall of the portion, extending into each positioning hole, of each connecting portion can be in contact with the inner wall of each positioning hole, and the inner wall of each positioning hole can limit the movement of each connecting portion along the direction perpendicular to the central line of the lower mask body.

Preferably, the mask further comprises an upper mask plate and a sucker device, the upper mask plate is used for being arranged at one end of the first surface, which is far away from the lower mask plate, the sucker device can absorb the surface of one side of the upper mask plate, which is far away from the lower mask plate, the surface of the other side of the upper mask plate can be contacted with the surface of the chip substrate, which is far away from one side of the lower mask plate, and the sucker device can drive the upper mask plate to move along the direction perpendicular to the first surface by moving along the direction perpendicular to the first surface.

Preferably, the number of the positioning pieces is 4, and the positioning pieces are uniformly arranged along a circular track taking the projection of the first axis on the first surface as a circle center.

Preferably, the surface of each positioning portion near one end of the connecting portion is in contact with the first surface, and the distance from the surface of each positioning portion far from one end of the connecting portion to the first surface is smaller than the thickness of the chip substrate.

Compared with the prior art, the utility model has the following technical effects:

the mask assembly is provided with a lower mask body and a positioning device, wherein the positioning device is provided with at least three positioning parts, the outer side wall of each positioning part is used for being in contact with the outer side wall of a chip substrate, the connecting line of the projection of the outer side wall of each positioning part on the first surface and the projection of a first axis on the first surface is a first line section, the included angle between any two adjacent first line sections is smaller than 180 degrees, the plurality of positioning parts can limit the movement of the chip substrate along the first surface, wherein the area surrounded by the plurality of positioning parts is the area where the chip substrate needs to be placed when the pattern of the chip substrate and the lower mask is aligned, namely a product placement area, and the plurality of positioning parts can limit the relative movement of the chip substrate and the lower mask body along the direction perpendicular to the central line of the lower mask body, namely the chip substrate is limited in the product placement area; the outer wall of the chip substrate between the two adjacent positioning parts is in a bare state, and the alignment of the chip substrate and the lower mask body can be achieved only by rotating the chip substrate through the outer wall of the chip substrate until the pattern of the chip substrate is aligned with the pattern on the lower mask body, so that the alignment of the chip substrate and the lower mask body can be completed under a microscope provided by a photoetching machine without moving the chip substrate along the surface of the lower mask body until the chip substrate is overlapped with a product placement area, the requirement on the field of vision of a microscope is reduced; the workload is reduced, the adjustment difficulty is reduced, and the improvement of the working efficiency is facilitated.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a lower mask plate in the present utility model;

FIG. 2 is a schematic view of a positioning member according to the present utility model;

in the figure: 100. a mask assembly; 1. a lower mask body; 101. a first surface; 102. positioning holes; 2. a positioning piece; 201. a positioning part; 202. a connection part; 3. a first line segment; 4. a product placement area; 5. and (5) aligning the mark.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The utility model aims to provide a mask assembly, which solves the problems in the prior art, reduces the requirement on the field of view of a microscope, reduces the workload and the adjustment difficulty, and is beneficial to improving the working efficiency.

In order that the above-recited objects, features and advantages of the present utility model will become more readily apparent, a more particular description of the utility model will be rendered by reference to the appended drawings and appended detailed description.

As shown in fig. 1-2, the present utility model provides a mask assembly 100, including a lower mask, where the lower mask includes a lower mask body 1 and a positioning device, the lower mask body 1 has a first surface 101, the positioning device is provided with at least three positioning portions 201, each positioning portion 201 is disposed on the first surface 101, and a plurality of positioning portions 201 are distributed around a first axis perpendicular to the first surface 101, a chip substrate is disposed on a portion of the first surface 101 in an area surrounded by the plurality of positioning portions 201, an outer sidewall of each positioning portion 201 is used to contact with an outer sidewall of the chip substrate, a connection line between a projection of an outer sidewall of each positioning portion 201 and a projection of the first axis on the first surface 101 is a first line segment 3, an included angle between any two adjacent first line segments 3 is less than 180 °, and the plurality of positioning portions 201 can limit movement of the chip substrate along the first surface 101. The mask assembly 100 provided by the utility model is provided with a lower mask body 1 and a positioning device, wherein the positioning device is provided with at least three positioning parts 201, the outer side wall of each positioning part 201 is used for contacting with the outer side wall of a chip substrate, the connection line of the projection of the outer side wall of each positioning part 201 and the projection of a first axis on the first surface 101 is a first line section 3, the included angle between any two adjacent first line sections 3 is smaller than 180 degrees, wherein the area surrounded by a plurality of positioning parts 201 is the area where the chip substrate needs to be placed when the chip substrate is aligned with the pattern of the lower mask, namely a product placement area 4, and the plurality of positioning parts 201 can limit the relative movement of the chip substrate and the lower mask body 1 along the direction perpendicular to the central line of the lower mask body 1, namely the chip substrate is limited in the product placement area 4; the outer wall of the chip substrate between the two adjacent positioning parts 201 is in a bare state, and the alignment of the chip substrate and the lower mask body 1 can be realized only by rotating the chip substrate through the outer wall of the chip substrate until the pattern of the chip substrate is aligned with the pattern on the lower mask body 1, so that the alignment of the chip substrate and the lower mask body 1 can be completed under a microscope provided by a photoetching machine without moving the chip substrate along the surface of the lower mask body 1 until the chip substrate is overlapped with the product placement area 4, the requirement on the field of vision of the microscope is reduced; the workload is reduced, the adjustment difficulty is reduced, and the improvement of the working efficiency is facilitated. The mask assembly 100 provided by the utility model is suitable for cylindrical chip substrates, and is particularly suitable for chip substrates with thicker thickness, such as ceramic blocks with the thickness of several millimeters to twenty millimeters.

Each positioning device comprises at least three positioning pieces 2, a plurality of positioning pieces 2 are distributed around a first axis, each positioning piece 2 comprises a positioning portion 201 and a connecting portion 202, one end of each connecting portion 202 is fixedly connected with each positioning portion 201, as a preferred embodiment, each connecting portion 202 and each positioning portion 201 are integrally formed, each connecting portion 202 and each positioning portion 201 are cylindrical, the other end of each connecting portion 202 is arranged on the lower mask body 1, and the outer diameter of each positioning portion 201 is larger than the outer diameter of each connecting portion 202. When each positioning portion 201 is cylindrical, the contact area between the positioning portion 201 and the chip substrate is a line segment parallel to the axis of the positioning portion 201. The outer diameter of each positioning part 201 can be adjusted according to the size of the outer wall of the chip substrate, and when the outer diameter of the chip substrate is larger, the outer diameter of each positioning part 201 is smaller; when the outer diameter of the chip substrate is smaller, the outer diameter of each positioning portion 201 is larger, so as to contact the outer wall of each positioning portion 201 with the outer wall of the chip substrate, and achieve alignment of the chip substrate and the product placement area 4.

It should be noted that, the structure of the positioning device in the present utility model is not limited to being composed of the positioning portion 201 and the connecting portion 202, and the following manner may be adopted: (1) The positioning piece 2 comprises an annular part and at least three positioning parts 201, each positioning part 201 is fixedly connected to one end of the annular part, the other end of the annular part is used for being connected with the lower mask body 1, an annular groove is formed in the lower mask body 1, the annular part stretches into the annular groove, the inner side wall and the outer side wall of the annular part are respectively and completely contacted with the two inner walls of the annular groove, namely, the annular part plays the role of a connecting part 202 and is used for enabling the positioning part 201 and the lower mask body 1 not to generate relative motion. (2) The positioning device is a positioning cylinder, a notch which is enough for operating the rotation of the chip substrate is formed in the side wall of the positioning cylinder, one end of the positioning cylinder is arranged on the lower mask body 1 and does not generate relative motion with the lower mask body 1, the other end of the positioning cylinder protrudes out of the first surface 101, at least three contact areas which are in contact with the outer wall of the chip substrate are formed in the inner wall of the positioning cylinder, and the contact areas are positioning parts of the positioning device and can limit the movement of the chip substrate on the first surface 101 up and down, left and right and the like, so that the chip substrate is placed in a product placement area; the superposition of the patterns on the chip substrate and the lower mask body 1 can be realized only by rotating the chip substrate through the notch on the positioning cylinder by a human hand. The positioning device provided by the utility model can limit the relative movement of the chip substrate and the lower mask body 1 along the direction perpendicular to the central line of the lower mask body 1 (the chip substrate is placed in the product placement area).

As a preferred embodiment, the lower mask body 1 is provided with at least three positioning holes 102, each connecting portion 202 is used for extending into each positioning hole 102, the outer wall of the portion of each connecting portion 202 extending into each positioning hole 102 can be in contact with the inner wall of each positioning hole 102, and the inner wall of each positioning hole 102 can limit the movement of each connecting portion 202 along the direction perpendicular to the central line of the lower mask body 1, so that after the positioning piece 2 is inserted into the positioning hole 102 of the lower mask body 1, the projection of the contact area of each positioning portion 201 with the chip substrate on the first surface 101 is always kept on the outer edge of the product placement area 4, thereby ensuring the accuracy of positioning the chip substrate. The connecting part 202 is limited through the positioning hole 102, so that the disassembly, assembly and replacement are convenient. It should be noted that, the connection portion 202 may also be fixedly connected with the lower mask body 1 to position itself, so as to position the chip substrate.

The mask assembly 100 further comprises an upper mask and a sucker device, wherein the upper mask is arranged at one end of the chip substrate, which is far away from the lower mask, the surface of one side of the upper mask, which is far away from the lower mask, can be fixedly connected with the sucker device, the surface of the other side of the upper mask can be contacted with the surface of one side of the chip substrate, which is far away from the lower mask, and the sucker device can drive the upper mask to move along the direction parallel to the center line of the lower mask by moving along the direction parallel to the center line of the lower mask. When in use, (1) the upper mask plate and the lower mask plate body 1 are put in the corresponding positions of the photoetching machine, and the alignment is completed by means of a microscope carried by the photoetching machine; as a preferred embodiment, the upper mask plate and the lower mask plate body 1 are provided with a plurality of alignment marks 5, such as cross-shaped alignment marks 5, the upper mask plate and the lower mask plate are initially aligned, and then the positions of the upper mask plate and the lower mask plate are further adjusted by means of a microscope, so that each alignment mark 5 on the upper mask plate is aligned with the corresponding alignment mark 5 on the lower mask plate, and the alignment of the upper mask plate and the lower mask plate is realized; (2) Starting the sucking disc device, enabling the sucking disc device to move downwards to be in contact with the upper surface of the upper mask plate and finish the adsorption of the upper mask plate, controlling the sucking disc device to move upwards and driving the upper mask plate to move upwards, wherein the distance of the upward movement is more than or equal to the space required by the chip substrate when the chip substrate is placed on the upper surface of the lower mask plate body 1; (3) placing a plurality of positioning members 2 into the corresponding positioning holes 102; (4) Placing the chip substrate in a product placing area 4 on the upper surface of the lower mask body 1, namely in the area among the plurality of positioning pieces 2, observing the patterns of the chip substrate and the lower mask body 1 by means of a microscope carried by a photoetching machine, and pinching the outer side wall of the chip substrate to rotate the chip substrate until the chip substrate is aligned with the patterns of the lower mask body 1; (5) The sucker device is controlled to move downwards and drive the upper mask plate to move downwards to be in contact with the upper surface of the chip substrate, and the upper mask plate and the lower mask plate body 1 still maintain an aligned state when the upper mask plate moves downwards to be in contact with the upper surface of the chip substrate because the sucker device moves along the direction parallel to the central line of the lower mask plate. Through the steps, the alignment of the upper mask, the chip substrate and the lower mask body 1 is realized, and then exposure and photoetching can be performed. In the photoetching process of the same product, the upper mask plate and the lower mask plate body 1 only need to be aligned once, the positioning piece 2 only needs to be installed once, and a plurality of chip base materials only need to be sequentially placed in a product positioning area for alignment and photoetching, so that the working efficiency is greatly improved.

As a preferred embodiment, the number of the positioning members 2 is 4, and the plurality of positioning members 2 are uniformly arranged along a circular track centered on the projection of the first axis on the first surface 101. The number of the positioning pieces 2 can be set according to the needs, so long as the good positioning of the chip base material can be satisfied, and the area between two adjacent positioning pieces 2 is enough to touch the outer side wall of the chip base material by fingers so as to rotate the chip base material.

As a preferred embodiment, the surface of each positioning portion 201 near one end of the connecting portion 202 contacts the first surface 101, and the outer wall of each positioning member 2 completely contacts the outer wall of the positioning hole 102, which can be achieved by reasonably setting the dimensions of the positioning hole 102 and the positioning member 2, for example, the dimensions of the positioning hole 102 are 1.6mm-1.603mm, and the outer diameter of the connecting portion 202 is 1.57mm-1.6mm, so that good positioning of the positioning member 2 is achieved, and further, positioning accuracy of the chip substrate is ensured; the distance from the surface of one end of each positioning part 201 far away from the connecting part 202 to the first surface 101 is smaller than the thickness of the chip substrate, so that the upper mask plate can be contacted with the upper surface of the chip substrate.

It should be noted that, in this embodiment, the materials and compositions of the upper mask plate and the lower mask plate body 1 are in the prior art, and the upper mask plate and the lower mask plate body 1 are transparent materials except for the mask pattern structure portion. The microscope of the photoetching machine is arranged at one end of the lower mask body 1 far away from the positioning device, and the field of view of the microscope can cover a partial area corresponding to the area surrounded by the positioning parts 201 on the lower mask body 1. When the mask is used, the chip substrate is placed on the lower mask body 1, and the outer wall of the chip substrate is contacted with the positioning surface, so that the chip substrate can be positioned along the direction vertical to the first surface 101; the chip substrate is rotated through the outer wall of the chip substrate under the microscope of the photoetching machine until the pattern of the chip substrate is aligned with the pattern on the lower mask body 1, specifically, the microscope of the photoetching machine can move left and right, when the photoetching pattern is simpler and regular, the outer edge of part of the pattern of the lower mask body 1 and the outer edge of part of the pattern of the chip substrate are observed through the lower mask body 1 by the microscope of the photoetching machine, if so, the whole pattern of the lower mask body 1 is aligned with the whole pattern of the chip substrate; when the photoetching patterns are complex, marks can be arranged at the corresponding positions of the lower mask body 1 and the chip substrate, and the marks can be observed by a microscope of the photoetching machine when the lower mask body 1 and the chip substrate are placed in the photoetching machine, and the alignment of the whole pattern of the lower mask body 1 and the whole pattern of the chip substrate is realized by aligning the marks of the lower mask body 1 and the chip substrate; the chip base material does not need to be moved along the surface of the lower mask body 1 until the chip base material coincides with the product placement area 4, so that the requirement on the field of view of a microscope is reduced, the workload is reduced, the adjustment difficulty is reduced, and the work efficiency is improved.

The principles and embodiments of the present utility model have been described in detail with reference to specific examples, which are provided to facilitate understanding of the method and core ideas of the present utility model; also, it is within the scope of the present utility model to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the utility model.

Claims (6)

1. A mask plate assembly is characterized in that: including lower mask, lower mask includes lower mask body and positioner, lower mask body has the first surface, positioner has at least three location portion, each location portion set up in on the first surface, and a plurality of location portion is around perpendicular to the first axis distribution of first surface, the chip substrate is used for placing a plurality of location portion is enclosed the regional part of formation on the first surface, the lateral wall of each location portion be used for with the lateral wall contact of chip substrate, the lateral wall of each location portion with the contact area of the lateral wall of chip substrate on the first surface with the projection of first axis on the first surface's link is first line section, and the contained angle between two arbitrary adjacent first line sections is less than 180, a plurality of location portion can restrict the chip substrate is followed the motion of first surface.

2. The reticle assembly of claim 1, wherein: each locating device comprises at least three locating pieces, a plurality of locating pieces are distributed around the first axis, each locating piece comprises a locating part and a connecting part, one end of each connecting part is fixedly connected with each locating part, the other end of each connecting part is arranged on the lower mask body, and the outer diameter of each locating part is larger than the outer diameter of each connecting part.

3. The reticle assembly of claim 2, wherein: the lower mask body is provided with at least three positioning holes, each connecting part is used for extending into each positioning hole, the outer wall of the part of each connecting part extending into each positioning hole can be in contact with the inner wall of each positioning hole, and the inner wall of each positioning hole can limit the movement of each connecting part along the direction perpendicular to the central line of the lower mask body.

4. The reticle assembly of claim 2, wherein: still include mask and sucking disc device, go up the mask be used for set up in first surface keep away from the one end of mask down, sucking disc device can be right go up the mask keep away from the surface of one side of mask down adsorbs, just go up the surface of the opposite side of mask can with the chip substrate is kept away from the surface contact of mask version body one side down, sucking disc device can be through following the perpendicular to the direction removal of first surface drives go up the mask along the perpendicular to the direction of first surface removes.

5. The reticle assembly of claim 2, wherein: the number of the positioning pieces is 4, and the positioning pieces are uniformly arranged along a circular track taking the projection of the first axis on the first surface as the center of a circle.

6. A reticle assembly according to claim 3, wherein: the surface of each positioning part, which is close to one end of the connecting part, is in contact with the first surface, and the distance from the surface of one end of each positioning part, which is far away from the connecting part, to the first surface is smaller than the thickness of the chip substrate.