JPS58143989A - Conveyor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conveying device used when there is a need for non-contact handling such as resist coating or evaporation.

Figure 1 shows a conventional method for removing objects without contacting the surface.

function of Bernoulli's equation used when

This shows a chuck that uses a chuck (1, hereinafter referred to as the Bernoulli chuck). Transport 1F'i.

An object (e.g. a wafer) that The pipe that sends compressed air in the 2-tube Bernunei Chasok body is 3, the leek.

It consists of a pull 4 and a jet hole 5. It is also a stopper for preventing lateral displacement of the object 1 having a 9° angle. Peru, the formula for 1° Nuy is expressed as. Here, P: pressure 9/-2 γ: specific weight of fluid Wtrl, v: flow velocity m/s, y: acceleration of gravity 9.8 m/z2. A: Height m from the reference plane
It is. When compressed air is sent to the Bernoulli chuck 2, the air is ejected from the ejection hole 5, hits the object 1, and the air flows out into the atmosphere like a streamline 6. In other words, in Equation (1), first, there is a case where there is a flow velocity and there is no flow velocity.

h is also equal, therefore, due to the flow velocity υ, the pressure p1 between the belter 11 and the object 10 is 7) I =
pQ −−u・・・・・・・・・・・・・・・
・・・・・・・・・(2) It is expressed as v, and it can be seen that the pressure is negative. Here, ・po indicates atmospheric pressure. Figure 2 shows the pressure distribution between the Bernoulli chat 2 and the object 1, so that the force due to the negative pressure and the air jet.

The sum of the pushing force and the weight of the object acts on object 1.

Relationship where the forces due to atmospheric pressure are equal / p+<x, y) dz + F +my -poA
−=−・−”−(s).

Object 1 is held by chuck 2 without surface contact.

Ru. Note that m: mass of object 1, A. Area of object 1,
F: Pushing force of the air jet section.

FIG. 3 summarizes the relationship of equation (3), where the vertical axis corresponds to the suction force of the chuck, and the horizontal axis corresponds to the force due to the negative pressure between the chuck and the bar. The bending force shown by the dotted line (you can see that the body can be absorbed. 1) Although the Bernoulli chuck operates based on the principle described above, the conventional system with an air outlet only in the center functions as an air bearing. This occurs only in the vicinity of this air outlet. Therefore, when an object is adsorbed, if an uneven load is applied to the object (for example, the mass distribution of the object is not uniform).

In the chuck/object surface state, the suction force is the chuck.

(Depending on location, etc.) with air bearings.

In the peripheral area where there is no force, the object will be attracted by the chuck.

come into contact with the surface.

For example, if the object is a wafer with a resist coated on its surface, the resist may be damaged, and the damaged resist may become dust.

This causes the wafers to stick to other wafers, resulting in lower product yields.

SUMMARY OF THE INVENTION An object of the present invention is to provide a conveying device that eliminates contact between an object and the chuck suction surface that occurs when a Bernoulli chuck picks up an object, and can handle the object without contacting the surface.

The feature of the present invention is that the compressed air outlet is set at 1°.

5 or more are installed on a suitable circumference from the center to increase the rigidity between the chuck and the object when picking up an object, and to prevent the airflow from each nozzle from interfering with each other and reducing the flow and speed. In order to prevent this, an appropriate hole is provided in the center of the chuck to create an escape route for air, and this configuration ensures that the above objective is achieved.

It has come.

The wafer is the workpiece that is transported by the wafer. wafer, 1.5
・ A semiconductor pattern of a mask (not shown) is transferred onto 1.
A resist is applied for baking, but this resist is fragile to mechanical shock and has the property of breaking into fine particles. The Bernoulli chuck main body 2 has an air supply section consisting of 5 to 4 air supply tubes 5, nipples 4, and jet holes 5 on a suitable medium diameter r, and the air ejected from each air supply section is connected to each other. An escape hole 7 is formed to allow the fluid to flow without interference. 8 is a lever II+ for vertically and rotating the Bernoulli chuck 2;
It is connected to each drive unit (not shown). This is a stopper that prevents the 9t-t wafer 1 from shifting laterally.

5 i-also the 4th
The figure shows the pressure distribution between the Ichak 2 and the Ueno 1 obtained by the present invention.

In the above configuration, the lever 8 to which the Bernoulli chuck 2° is fixed is first set against the Ueno 1.

Descend to the position. At this time, air is supplied to tube 3.

I'll stop it. Next, when air flows into tube 3, the air becomes 1.
4. Passing through the spout 5, one side is immediately exposed to the atmosphere (the other side is
The other side flows out into the atmosphere through the escape hole 7 of the Bernoulli chuck 2. As a result, there is a gap between the Bernoulli chuck 2 and the wafer 1 as shown in FIG.

As a result, a modified form of basic equation (3) ゛Σ
fpin(x,y)r1g+ΣFi+rai-po(A
-A') =-・Shiwafer 1 is Bernoulich under the condition that (4) holds true.

It is adsorbed to Yak 2 without contacting the surface. Please note that pirL”(
T, 31); Negative pressure distribution obtained at each air supply section, Fl
・：Pushing force of air jet part generated in each air supply part, 10A
'z Pernoud - f chuck escape area is large.・In this case, when the wafer 1 is attracted to the Bernoulli chuck 2, an unbalanced load is generated on the wafer 1. ・Even if an uneven load is generated on the wafer 1, the pushing force of the air jet section of each air supply section, that is, the air bearing in FIG. The effect is chat.

Wafer 1 acts on the outer periphery rather than the center.

Do not touch the suction surface of Bernoulli Chuck 2.

It won't fly.

The present invention has one or more of the configurations and functions described above.

According to the present invention, since the present invention has a plurality of air supply sections and has a distance of 1°, even if an unbalanced load occurs during wafer adsorption, the pushing force of the plurality of air supply sections will prevent the wafer surface from colliding with the chuck adsorption surface. Since there is no contact between the resists and the resist on the wafer surface, there is no possibility of damaging the resist on the wafer surface, which has the effect of significantly improving the yield of semiconductor manufacturing.

[Brief explanation of drawings]

Figure 1 shows a cross-section of a conventional Bernoulina yak. FIG. 5 is a cross-sectional view showing the Nouiteyac, and is also an explanatory view showing the pressure distribution between the chuck and the wafer. 1...Object. 2... Bernoulli Chatta body, 1.3
...Fluid supply pipe, 4...Nipple, 5...
Fluid spout, 6... Fluid streamline, 7... Relief hole, 8... Lever 9... Stopper to prevent side shift of object. Agent Patent Attorney Susuki 1) Yuki Toshi 1.1・7・f 1 Figure 2Z[B Negative pressure ↑ Positive pressure Sai j Zuzai Do Figure 7 5 Positive L to group

Claims (1)

[Claims] 1. In a mechanism that supplies fluid to create negative pressure to adsorb and transport an object, there are six or more flow and volume outlets and a fluid flow outlet that prevents the fluid flowing from each of the fluid jet ports from interfering with each other. A conveying device characterized by having an escape hole.