JPS58173746A - Coater of photoresist - Google Patents

Abstract

PURPOSE:To enable selective and easy coating of a resist, by providing an observing device which observes defects and a resist dropper which drops the resist to the defect of a negative type among the defects. CONSTITUTION:A resist coater has a table device 20, a control device 29 of the device 20, a resist dropper 30 for dropping a resist and a microscope 40 for observation of the dropping point of the resist. The device 29 is constituted of driving devices 23X, 23Y which move a stage 22 in X-, Y-directions, micrometers 24X, 24Y which measure the moving distances of the stage 22 in the X-, Y- directions and a controller 25 which operates the devices 23X, 23Y according to the data inputted from a terminal T7 or the output of the micrometers 24X, 24Y and displays the moving stage of the stage 22 on a display 25D. The dropper 30 consists a discharge nozzle 31, a filter 35 for filtration of a resist 13, a supply pump 36, a bolt 37, and a pulse generator 34.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus used in a photoetching process, which is mainly used in the manufacturing process of semiconductor devices such as ICs and LSIs, and particularly relates to a photoresist coating apparatus for correcting defects in a developed resist pattern. equipment (hereinafter simply referred to as “
(referred to as "resist coating device").

A photoetching process conventionally performed in the manufacturing process of semiconductors is generally as shown in FIGS. 1(A) to 1(G). The substrate 10 to be photoetched includes a base 1
1 and a film 12 on which pattern formation is performed (see figure (A)), and is first heat-treated to improve adhesion to a positive photoresist (hereinafter simply referred to as "resist") 13 or to remove adsorbed materials. will be applied. Next, the same figure (
A resist 13 is applied as shown in B), and prebaked to remove the solvent remaining in the resist 13.

Next, as shown in FIG. 2C, exposure is performed through a suitable mask 14. Note that when the resist 13 is of negative type, a mask 14N is used (see (D) in the same figure). After this exposure, development is performed with an appropriate solvent, and the mask 1
The resist 13 is formed into a pattern of 4 (or mask 14N) (see FIG. 4(E)). Thereafter, in order to improve the adhesion between the resist 13 and the film 12, a boss bake is performed, and further etching is performed, resulting in the state shown in FIG. 3(F). If the remaining resist 13 is removed here, the state shown in FIG. 3(G) is obtained, and the film 12 is formed in the pattern of the mask 14.

However, defects D1 to D5 as shown in FIG. 2(A) exist in the resist pattern shown in FIG. 1(E).

Then, defects El to E5 as shown in FIG. 2(B) also appear in the pattern of the film 12. In particular, in substrates used for large-area image sensors used in copiers and the like equipped with thermal heads, defects El to E5 are present due to the characteristics of a device that functions as a single unit of functional element. is unacceptable.

On the other hand, as the area of the device increases, such defects El to E5 will appear somewhere, and in order to improve the yield, some means for correcting the resist pattern is required.

As such a correction method, a method of performing the resist pattern formation process twice or a method of using two layers of positive resist and negative resist are proposed, but the types and abundance of defects Dl to D5 have been proposed. Since this is done without any consideration given to the resist pattern, it is not possible to satisfactorily modify the resist pattern.

This invention has been made in view of the above circumstances, and by simply and easily performing selective coating of resist in the resist pattern modification process, the resist pattern modification work can be performed with high precision, and as a result, the device An object of the present invention is to provide a resist coating device that can improve yield.

That is, in the present invention, a substrate having a defect is placed on a table device having a two-dimensionally movable stage, the stage is moved by a control device based on data representing the position of the defect, and the stage is moved by an observation device. By selecting only certain defects and dropping and applying resist using a resist dropping device, it is possible to simply and easily apply resist selectively in a resist pattern correction process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A resist coating apparatus according to the present invention will be described in detail below according to embodiments shown in the accompanying drawings.

FIG. 3 shows an example of the structure of resist coating according to the present invention. In this figure, the resist coating device includes a table device 20, a control device 29 for the table and the device, a resist dropping device 130 for dropping resist, and a microscope 40 that is a device for observing the resist dropping point. are doing.

First, the table device 20 has a base 21 that is horizontally fixed as appropriate, and arrows FX (hereinafter this direction will be referred to as the "X direction") and arrows FY (hereinafter this direction will be referred to as "X direction") in the figure with respect to this base 21.
The stage 22 is arranged to be movable in the "Y direction".

Next, the control device 29 includes drive devices 23X and 23Y that move the stage 22 in the X and Y directions, a micrometer 24X124Y that measures the moving distance of the stage 22 in the X and Y directions, and a terminal. The controller 25 operates the driving devices 23X, 23Y according to data input from T1 or the outputs of micrometers 24X, 24Y-, and displays the moving state of the stage 22 on a display section 25D.

Of these, the driving devices 123X, 23Y and the micrometers 24X12-4Y are arranged at appropriate positions on the table device 20, and the driving devices M23X, 23Y are provided with handles HX, HY, respectively, so that they can be manually operated. Therefore, the stage 22 can be moved.

On the other hand, the resist dropping device 30 includes a discharge nozzle 31, a filter 35 for filtering the resist 13, a supply pump 36, a bottle 37, a pulse generator 34, and the like. The resist 13 housed in the bottle 37 is
It is sent out by a supply pump 36, filtered to remove impurities and the like by a filter 35, and further supplied to a tank 33 in a discharge nozzle 31. A piezoelectric element 32B is arranged in the upper part of this discharge nozzle 31 so as to be in contact with the tank 33 via a diaphragm 32D, and the output pulse of the pulse generator 34 is applied to the piezoelectric element 32B. ing. That is, when one pulse is applied to the piezoelectric element 32B, the piezoelectric element 32B expands due to the piezoelectric effect. Since this is transmitted to the tank 33 via the diaphragm 32D, the volume of the tank 33 is slightly reduced. Therefore, a droplet of the resist 13 corresponding to this decrease is ejected to the outside.

A switch (not shown) is connected to the terminal T2 of the pulse generator 34, and pulses are output when this switch is operated by the operator. Further, the dropping point of the resist 13 dropped from the discharge nozzle 31 is set to be approximately at the center of the base 21.

11 Also, the microscope 40 is similar to a normal one, and the dropped resist 13 is within its field of view, and the microscope 40 is similar to the normal one. The dropping point is arranged to be the cross point of a cross-shaped scale 41 provided on the eyepiece lens in contact with the naked eye ME.

Next, an exposure means for selectively exposing the portions on which the resist 13 is selectively applied by the resist coating device will be explained. FIG. 4 shows an example of a correction mask means for performing such selective exposure, which includes a mask 50 (hereinafter referred to as "positive mask") that allows light to pass through only a certain area;
A mask 60 (hereinafter referred to as a "negative mask") that blocks light only in a certain area. First, the positive mask 50 consists of a fixed plate 51 made of an abbreviated piece, a movable plate 52 movable in the direction of arrow GXh in the figure, and a movable plate 53 movable in the direction of arrow GYh in the figure. There is.

An opening OP is formed by one side of these movable plates 52.53 and the concave side of the fixed plate 51, and the size of this opening OP can be adjusted as appropriate by moving the movable plates 52.53. It has become.

Next, the negative mask 60 is made of a material that is transparent to the light used for exposure, and has an opaque tip 61 of an appropriate size formed approximately in the center thereof.

Next, the overall operation of the above embodiment will be explained with reference to FIGS.
In addition to the figure, while referring to Figures 5 and 6, Figure 2 (A
The correction of defects Dl to D5 shown in > will be explained as an example. Note that FIGS. 5A to 5E are plan views showing examples of combinations of resist pattern correction and exposure masks;
The figure is a flowchart showing the modification procedure, with region 1 representing the conventional etching process and region 2 representing the modification process.

First, if the defects Dl to D5 in FIG. 2(A) are shown again in plan, they are as shown in FIG. 5(A).
The state corresponds to FIG. 1(E), and the steps of coating the resist 13, prebeta, exposing, and developing have already been completed (see FIG. 6).

Here, the substrate 10 is subjected to a defect inspection device (not shown), and the presence or absence of defects D1 to D5 and their positions are obtained as data. This data is expressed, for example, as coordinates (χ, y) whose origin is the alignment mark TM (see FIG. 3) on the substrate 10 used for mask alignment. Therefore, the scale of the coordinates (X, Y) representing the position of the dropping point of the resist dropping device 30 of the resist coating device is made to correspond to the (χ, y), and the origin of the coordinates (X, Y) is set to the alignment mark. TM, and by placing the substrate 10 on the stage 22 with the same directionality as in the defect inspection device and adjusting the parallelism, the control device 29 can perform a correction coating operation of the resist 13. That is, by inputting data representing the positions of defects Dl to D5 in the defect inspection apparatus to the controller 25 and moving the stage 22, the defects Dl to D5 are detected by resist dropping 1@3.
The position of the substrate 10 on the stage 22 is determined so as to be the dropping point of zero or the cross point of the scale 41 of the microscope 40. This eliminates the need for the operator to use the microscope 40 to search for defects D1 to D5.

Next, the operator uses the microscope 140 to detect defects Dl to D.
5 are sequentially observed, and the resist 13 is applied dropwise only to the defects D1 and D3 (hereinafter collectively referred to as [negative defects]) using the resist coating device 30. Note that the amount of the resist 13 to be dropped can be adjusted by changing the size of the piezoelectric element 32B or the size and width of the pulse applied thereto. The viscosity of 13 can be adjusted. The state after this dropping is shown in 5th Fl (13). As shown in the figure, the defect D1 is corrected to become a repaired portion S1, and the defect D3 becomes a repaired portion S3 in which the resist 13 protrudes to the outside.

Next, the substrate 1 on which the above-described corrective coating of the resist 13 has been applied
0, prebaking is performed.

After this prebaking, the substrate 10 is selectively exposed to light using a correction mask means shown in FIG. Which of the positive mask 50 and the negative mask 60 is used depends on the type of defect. First, regarding the correction portion 83 (see FIG. 5(B)) of the defect D5 or defect D3, as shown in FIG. Further, the original correct resist pattern is masked using a negative mask 60 to expose the corrected portion S3, and then exposure is performed.

Similarly, regarding the defect D4, the edge-shaped mask 50
, select the area including the defect D4, and then use the corner of the tip 61 of the negative mask 60 to
4 and perform exposure (see FIG. 5(D)).

Next, regarding the defect D2, using only the positive mask 50, the defect D2 is exposed and exposed (see Fig. 5 (E).
)reference).

Further, regarding the defect D1, since the resist 13 is applied to form the repaired portion S1, there is no need to perform any exposure.

After performing the above selective exposure, the substrate 10 is developed. As a result, the defects D2, D4, D5 and the correction section 83
(hereinafter collectively referred to as "positive defects") have been removed, and since the defect D1 has already been corrected, the resist pattern is successfully corrected as shown in FIG. 1(E).

Note that although the above example is a case where a positive type resist 13 is used, the same applies to a case where a negative type resist 13N is used. The developer should be positive.

First, it is assumed that the resist pattern shown in FIG. 5(A) is formed using a negative resist 13N. For the defect D1, a positive resist 13 may be dropped. Next, the resist 13 may be similarly applied to the defect D3, and the repair portion S3 may be repaired in the same manner as described above. Since the negative resist 13N is insoluble in the positive developer, it does not affect other patterns.

If defects D2, D4, and D5 are caused by poor development, they can be corrected by performing development again using a negative developer. If these defects are caused by erroneous light irradiation due to poor exposure, for example, a defect in the mask 14N, it is impossible to correct them and it is necessary to form the entire resist pattern again (see Figure 1). (See (D)). In other words, although it is possible to correct the resist pattern using the negative resist 13N within a certain range, there are defects that cannot be corrected because the defects cannot be removed by exposure for correction. On the other hand, when modifying a resist pattern using the positive resist 13, any number of parts of the pattern can be removed by performing exposure for modification, so there are no uncorrectable defects. That is, the present invention is particularly effective in correcting a resist pattern using the positive resist 13, and although the resist used for correction may be a negative resist, using a positive resist causes correction failures. Good modifications can be made without any danger.

Further, in the above embodiment, the negative mask 60 is placed on the positive mask 50, but if a predetermined exposure pattern can be obtained, the arrangement may be reversed, or only one of them may be used. good. In addition, various shapes of openings O
It is also possible to prepare a positive type mask having P and a negative type mask having tip portions 61 of various shapes, and to use these in appropriate combination. ) or masks 14 and 14N shown in (D) may be used in combination. Furthermore, when the number of defects D1 to D5 is small and their positions are clear, it is more efficient to manually position the dropping point of the resist 13 by operating the handles HX and HY.

In addition, at the position where the prototype was made regarding this invention, several 10C
When the resist 13 having a viscosity of about P was used, the spread on the substrate 10 was about 50 to 100 μm.

As explained above, according to the resist coating apparatus according to the present invention, a substrate having a defect can be placed on a table device having a two-dimensionally movable stage, and the position of the defect can be determined. Based on the data represented by the control device, ! , ≧ Since the stage is moved, only negative defects are selected by the observation device, and the resist is dropped and coated by the resist dropping device, selective coating of the resist in the resist pattern correction process is simple and easy. Furthermore, it has the excellent effect of being able to perform the process with high precision and, as a result, improving the yield of devices.

[Brief explanation of drawings]

Figures 1 (A> to (G)) are perspective views showing the state of the substrate during the photoetching process, and Figures 2 (A) and (B)
3 is a perspective view showing how a defect occurs, FIG. 3 is a perspective view showing an example of the configuration of a resist coating apparatus according to the present invention, and FIG.
The figure is a perspective view showing an example of the configuration of a correction mask means used in the present invention, FIGS. 1 is a flowchart showing the steps of a resist pattern correction method. 10...Substrate, 13...Resist, 20...Table device, 22...Stage, 29...Control device,
30...Resist dropping device, 32B...Piezoelectric element,
Dl, D3...Negative type defects.

Claims (2)

[Claims] (1) A table @stomach that is two-dimensionally movable and has a stage on which a substrate with a defect in the resist pattern is placed, and the movement of the stage is controlled according to data indicating the defect position 1 of the substrate. A photoresist coating apparatus comprising: a control device; an observation device for observing the defects; and a resist dropping device for dropping resist onto negative defects among the defects. (2) The photoresist coating device according to claim 7, wherein the resist dropping device is a resist dropping device that discharges resist by the piezoelectric effect of a piezoelectric element.