JPH07114183B2 - Resist coating apparatus and resist coating method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a resist coating apparatus and a resist coating method for coating a resist on the surface of an object to be treated.

(Prior Art) Conventionally, in a manufacturing process of electronic components such as a semiconductor wafer, a resist is applied as a pre-process of an exposure process.

FIG. 3 is a diagram showing a structure of a resist coating apparatus for manufacturing a semiconductor wafer as a resist coating apparatus used in the manufacturing process of such an electronic component. At the lower end of the bellows 1 for pumping the resist, A resist introducing pipe 3 is attached via a check valve 2. This resist introduction tube 3
Is inserted in a resist storage tank (not shown), and the resist introduced into the bellows by the expansion of the bellows 1 is pressure-fed through the resist supply pipe 4 attached to the upper end of the bellows 1 to discharge the resist (not shown). And is dropped onto an object to be processed, for example, a semiconductor wafer.

A bellows expansion / contraction mechanism such as an air cylinder 5 is attached to the lower end of the bellows 1, and the operation of the air cylinder 5 causes the bellows 1 to expand / contract.

Adjustment of the resist coating amount in such a resist coating apparatus is performed by adjusting the stroke of the air cylinder 5. The stroke is adjusted by the limit switch of the UP / DOWN sensor 6 provided at the lower end of the air cylinder. That is, stroke adjustment is performed by adjusting the distance between the UP limit switch 7 that limits the upper limit of the air cylinder 5 and the DOWN limit switch 8 that similarly limits the lower limit.

In the resist discharging operation in the resist coating apparatus having such a structure, first, the bellows 1 is expanded and contracted several times to introduce the resist into the bellows 1, and then the air cylinder 5 is moved to the UP limit switch 7 as shown in FIG. The bellows 1 is shrunk by stretching it up to
The bellows 1 is expanded by contracting the air cylinder to the DOWN limit switch 8 again. The resist discharge amount at this time is the stroke of the air cylinder 5, that is,
Determined only by the distance between UP limit 7 and DOWN limit 8 of UP / DOWN sensor 6.

(Problems to be Solved by the Invention) However, in the above-described conventional resist coating apparatus, since the resist discharge amount is determined only by the stroke of the air cylinder, it depends on the type of the object to be processed such as the semiconductor wafer and the manufacturing process. In addition, it is difficult to adjust the coating amount at any time, and there is a problem that the resist is wasted and it is uneconomical.

For example, when applying a resist to a semiconductor wafer,
As shown in the figure, the amount of resist applied varies depending on the type of the semiconductor wafer 9, and the semiconductor wafer having a smooth surface (
In FIG. (A)), even if the coating amount is, for example, 0.6 cc, in the case of a semiconductor wafer with many irregularities 10 on the surface (FIG. 5 (b)),
A coating amount of 1.2cc is required. However, in the conventional apparatus, since the stroke of the air cylinder is set for 1.2 cc, extra resist is applied in the case of a smooth semiconductor wafer, resulting in waste of the resist.

In order to solve this problem, it is possible to change the stroke at any time according to the object to be processed, but in the manufacturing process that supports recent small-lot production of a wide variety of products, the frequency of adjustments becomes extremely high, and workability is improved. And deterioration of production efficiency.

Further, in the conventional resist coating apparatus, there is a problem that air bubbles are mixed into the resist and the production efficiency is deteriorated.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a resist coating apparatus and a resist coating method capable of preventing bubbles from entering the resist and improving production efficiency. And

[Structure of the Invention] (Means for Solving Problems) A resist coating apparatus according to the present invention is a resist coating apparatus configured to discharge a resist onto an object to be processed through a bellows. When supplying the resist, a bellows expansion and contraction mechanism that expands and contracts the bellows a plurality of times, and when supplying the resist from the bellows to the object to be processed, based on the expansion and contraction amount of the bellows in advance, An operation control mechanism for controlling the operation of the bellows in consideration of the amount supplied to the object to be processed.

Further, the resist coating method of the present invention is a resist coating method in which the resist is discharged onto the object to be processed through a bellows, and when the resist is supplied into the bellows, the resist is stretched a plurality of times and introduced into the bellows Based on the amount of expansion and contraction of the bellows in advance, in view of the amount supplied to the object to be processed, the bellows is expanded and / or contracted to discharge the resist from inside the bellows onto the object to be processed. And a step of performing.

(Operation) In the resist coating apparatus and the resist coating method of the present invention,
By preliminarily expanding and contracting the bellows a plurality of times so that the resist is introduced into the bellows, it is possible to prevent air bubbles from entering. This can improve the production efficiency.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

At the lower end of the bellows 11 that pressure-feeds the resist, a resist insertion pipe 14 having one end inserted into the resist storage tank 13 via a check valve 12 is attached, while at the upper end of the bellows 11,
Resist supply pipe with resist discharge part 15 attached to the tip
16 is attached via an air operated valve 17. The expansion / contraction operation of the bellows 11 is performed by expansion / contraction of a bellows expansion / contraction mechanism provided at the lower end of the bellows 11, for example, an air cylinder 18.

The air cylinder 18 is provided at the lower end of the air cylinder, and includes a DOWN limit switch 19 that limits the lower limit of the air cylinder, and a resist discharge amount control unit 20 that controls the operating time of the air cylinder 18 to adjust the resist discharge amount. Its operation is controlled.

The resist discharge amount control unit 20 includes a resist discharge amount setting mechanism 2
1. A discharge amount-bellows operation time calculation mechanism 22 and a bellows operation control mechanism 23, which control the operation time of the air cylinder 18 in accordance with a desired discharge amount.

In the operation of the resist coating apparatus having such a configuration, first, the bellows 11 is expanded and contracted several times in advance so that the resist is introduced into the bellows, and then the resist discharge amount setting mechanism 21 according to the semiconductor wafer 24 to be processed. The desired discharge amount is set by.

The discharge amount setting information is converted into the operation time of the bellows 11, that is, the operation time of the air cylinder 18 by the conversion parameter stored in the discharge amount-operation time calculation mechanism 22 and input to the operation control mechanism 23. Drive the air cylinder 18,
The resist in the bellows 11 is pumped.

The resist dropped in a predetermined amount on the semiconductor wafer 24 in this way is uniformly dispersed on the semiconductor wafer 24 by, for example, a centrifugal force generated by the rotation (for example, 1000 rpm) of the rotary table 25 on which the semiconductor wafer is placed.

In the resist coating apparatus having such a structure, the amount of resist discharged is adjusted by the air cylinder 18 as shown in FIG.
Can be arbitrarily adjusted depending on the operating time of, that is, the operating time of the bellows.

Therefore, the resist discharge amount can be easily adjusted for each type of semiconductor wafer and each working process, waste of the resist is eliminated, and workability is improved. When using this device,
It is possible to save 30-40% of resist compared to the conventional system.

By the way, if the type of semiconductor wafer to be processed is stored in advance in the resist discharge amount control unit in the order of work steps, or if the resist discharge amount control unit 20 and the CPU for managing the production line are online, the resist discharge amount for each work No need for adjustment and complete automation of work is possible.

[Structure of the Invention] As described above, according to the resist coating apparatus and the resist coating method of the present invention, it is possible to prevent bubbles from being mixed into the resist, so that the production efficiency is improved by further simplifying the work.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a resist coating apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing a bellows operation in the embodiment, FIG. 3 is a diagram showing a configuration of a conventional resist coating apparatus, and FIG. FIG. 5 is a view showing the operation of the bellows in the conventional apparatus, and FIG. 5 is a sectional view showing the resist applied to the semiconductor wafer. 11 …… Bellows, 13 …… Register storage tank, 18 …… Air cylinder, 20 …… Regist discharge amount control unit, 21 …… Regist discharge amount setting mechanism, 22 …… Discharge amount-operating time calculation mechanism,
23 ... Operation control mechanism, 24 ... Semiconductor wafer.

Claims (2)

[Claims] 1. A resist coating apparatus configured to discharge a resist onto an object to be processed through a bellows, wherein the resist is supplied into the bellows by expanding and contracting the bellows a plurality of times. When supplying the resist to the object to be processed from the bellows, the operation of the bellows is controlled based on the amount of expansion and contraction of the bellows in advance in consideration of the amount to be supplied to the object to be processed. A resist coating apparatus comprising an operation control mechanism. 2. A method of applying a resist onto a target object through a bellows, wherein the resist is supplied into the bellows, and the resist is expanded and contracted a plurality of times to introduce the resist into the bellows. Discharging the resist from inside the bellows onto the object to be processed by stretching or / and contracting the bellows based on the amount of expansion and contraction of the bellows in consideration of the amount supplied to the object to be processed. A resist coating method characterized by the above.