JPH03283422A - Projection exposure device - Google Patents

Abstract

PURPOSE:To manufacture the title projection exposure device capable of focussing without changing the magnification by a method wherein a reticle and a projecting lens are displaced so that the specific relations between the displacement amount of reticle, that of projecting lens and the magnification of projected image of reticle may be almost satisfied. CONSTITUTION:The title projection exposure device equipped with a light source 10, a reticle 20 irradiated with the light emitted from the light source 10 and a projecting lens 30 projecting the image on the reticle 20 is additionally equipped with a reticle position adjusting mechanism 40 adjusting the position by displaying the reticle 20 in the optic axis P direction, a projecting lens position adjusting mechanism 50 adjusting the position by displacing the projecting lens 30 in the optic axis P direction as well as a displacing mechanism 60 displacing the reticle 20 and the projecting lens 30 almost satisfying the relations represented by a formula I. Within the formula I of Z1=(1+1/M) Z2, Z1, Z2 and M respectively represent the displacement amount of the reticle 20, that of the projecting lens 30 and the magnification of the projected image of the reticle 20.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to, for example, T A B (Tape Auto
The present invention relates to a projection exposure apparatus suitable for manufacturing a film circuit board used for mounting electronic components using a bonding method.

[Conventional technology]

Photolithography technology is known as a technology for applying microfabrication to the surface of an object. In addition to semiconductor integrated circuits, this technology has recently been applied to the production of film circuit boards used for mounting electronic components using the TAB method.

Photolithography involves an exposure process for transferring a pattern on a photomask, and a projection exposure device with a built-in photomask is used in this exposure process.

In a projection exposure apparatus, before starting actual exposure, work is performed to focus and magnify a projected image. This focusing and magnification adjustment is performed, for example, by the method described in Japanese Patent Application Laid-Open No. 1-191493, while monitoring images of patterns, alignment marks, etc. projected on the exposure surface with a monitor system.
Focusing and the like are performed by moving the projection lens position adjustment mechanism and the photomask position adjustment mechanism in the optical axis direction.

[Problem to be solved by the invention]

However, in conventional devices, when the projection lens position adjustment mechanism or photomask position adjustment mechanism is operated to displace the position of the projection lens or photomask in the optical axis direction for focusing, the magnification of the projected image is increased. also changed,
Even if you set the magnification correctly in advance, the magnification will be incorrect after focusing. Therefore, it is necessary to adjust the magnification again. If the projection lens position adjustment mechanism or photomask position adjustment mechanism is operated to adjust the magnification, the focus that has been carefully adjusted will shift, so another focus adjustment operation is required.

In this manner, with conventional devices, it is impossible to correctly focus and magnify unless the focusing and magnification adjustment are alternately repeated many times.

Therefore, there was a problem in that it took a very long time to adjust the focus and magnification.

An object of the present invention is to provide a projection exposure apparatus that can perform focusing without changing magnification.

Another object of the present invention is to provide a projection exposure apparatus that can change magnification while maintaining focus.

[Means to solve the problem]

In order to achieve the above object, a projection exposure apparatus of the present invention includes a light source, a reticle to which light from the light source is irradiated, and a projection lens for projecting an image of the reticle. It has a reticle position adjustment mechanism that adjusts the position by displacing the projection lens in the optical axis direction, and a projection lens position adjustment mechanism that adjusts the position by displacing the projection lens in the optical axis direction. When the amount is ΔZ2 and the magnification of the projected image of the reticle is M, ΔZl = (1+) ΔZ *
The present invention is characterized in that it includes a moving mechanism that moves the reticle and the projection lens so as to substantially satisfy the relationship (a).

In another projection exposure apparatus of the present invention, the moving mechanism is ΔZl =
(1--) ΔZ2 ””' (b)
The reticle and the projection lens are moved so as to substantially satisfy the following relationship.

[Effect]

When the reticle and the projection lens are moved by the movement mechanism so that the relationship of equation (a) above is approximately satisfied, the magnification of the projected image can be kept constant without changing and the focus can be adjusted.

Further, by moving the reticle and the projection lens using the moving mechanism so as to substantially satisfy the relationship of equation (b) above, it is possible to change the magnification of the projected image while keeping the lens in focus.

〔Example〕

The present invention will be explained in detail below.

11th! I is an explanatory diagram of a projection exposure apparatus according to an embodiment of the present invention. First, an embodiment of the invention of claim (1) will be described.

In this embodiment, as shown in FIG.
In a projection exposure apparatus that includes a reticle 20 that is irradiated with light from a light source 10 and a projection lens 30 that projects an image of the reticle 20, a reticle whose position is adjusted by displacing the reticle 20 in the direction of the optical axis P. The position adjustment mechanism 40, the projection lens position adjustment mechanism 50 that adjusts the position by displacing the projection lens 30 in the direction of the optical axis P, and the reticle 20 and the projection lens 3 so as to substantially satisfy the relationship of equation (a) above.
A moving mechanism 60 for moving 0 is provided.

The movement mechanism 60 includes a control unit 61 containing a CPU and RAM, a forward direction button 62 for moving the reticle 20 in a direction approaching the light source 10, a negative direction button 63 for moving the reticle 20 in the opposite direction, and a numerical input button. A section 64 and line manpower 65 are provided.

Reference numeral 71 denotes a microscope pair 2, which constitutes a projection image monitoring system. F is film, 81
is a feed roller, 82 is a sprocket roller, 83, 84
are press rollers, and the film F is step-fed frame by frame to the projection position by these rollers.

FIG. 2 is an illustration of formulas (a) and (ra) in the example. As shown in FIG. 2, the distance from the film F to the reticle 20 is 21, and the distance from the film F to the projection lens 3 is
When the distance to the center 30C of 0 is 22, the distance from the reticle 20 to the first principal plane 30A of the projection lens 30 is A, and the distance from the second principal plane 30B of the projection lens 30 to the film F is B, then zI displacement ΔZ1 and displacement ΔZ2
The relationship between Z2, the displacement ΔA of A, and the displacement ΔB of B is as follows. However, the displacement in the direction approaching the light source <second
In the figure, upward displacement) is considered positive.

ΔA=ΔZ, -ΔZ2 (+)ΔB=
Δ22 −−−−−−−−−−−− (ii) Here, since the magnification M of the projected image is B/A, B = M
A---(iii).

Although the image is an inverted image, it is assumed that M>0.

Differentiating this equation (iii) with respect to A yields A. Here, when ΔA and ΔB are minute amounts, d
Since A=ΔA and dB=ΔB, ΔB=MΔA(
1v). Substituting equations (i) and (11) into equation (IV) yields ΔB-M (Δz1-Δz2)-△z2, and rearranging this results in ΔZl = N+-)ΔZ2, which is (a) It is the same as the expression.

From the above, conversely, if Δz1 and ΔZ2 are moved so as to substantially satisfy the relationship in equation (a), it is possible to focus while keeping the magnification M constant.

Therefore, in the projection exposure apparatus according to the embodiment of claim (1), the system area of the memory such as the RAM in the control unit 61 constituting the moving mechanism 60 stores a program for calculating the above equation (a). ing.

In the projection exposure apparatus of this embodiment, focusing can be performed as follows.

■ From the reticle 20 to the first principal plane 30 of the projection lens 30
A and the distance B from the second principal plane 30B to the film F are entered in advance by the control unit 6 using the numerical input unit 64.
1, and the value of the magnification M (B/A) is calculated and stored.

(2) Next, for example, when the forward direction button 62 is pressed, a signal is sent to the control section 61 to move the projection lens 30 a predetermined distance (ΔZ2) in the forward direction toward the light source 10 according to the time of pressing.

(2) The CPU of the control unit 61 calculates the value of Δz1 from the pre-stored magnification M and ΔZ2 manually input using the forward direction button 62 based on the above equation (a).

■ Signals corresponding to the above △z1 and △z2 are sent to the reticle position adjustment mechanism 40 and the projection lens position adjustment mechanism 50, which adjust the reticle 20 and the projection lens 3.
0 is moved in the direction of the optical axis P. During this movement, the magnification M is maintained at a constant value according to the above equation (a).

■ Also, if you press the negative direction button 63, the positive direction button 6
In the opposite direction to when pressing 2, that is, the projection lens 3
0 in the negative direction away from the light source 10 by a predetermined distance (△Z2'
) A signal for movement is sent to the control unit 61, and the reticle 20 and projection lens 30 are moved in the direction of the optical axis P in the same manner as described above.

■ In this way, the reticle 20 and the projection lens 30
As B moves, the value of B changes. Therefore, while observing the projected image of the reticle 200 through the microscope 72, the operator performs a movement operation using the positive direction button 62 or the negative direction button 63 when the projected image becomes the clearest. Once this is completed, the value of equation (C) above will match 1/f, and the focus will be on.

In addition, when it is possible to estimate in advance how much the projection lens 30 should be moved to achieve focus, ΔZ2 can be input from the numerical input section 64.
After making a rough adjustment by inputting the value of , focusing can be performed in a short time by fine adjustment using the positive direction button 62 or the negative direction button 63.

Note that the line manual input 65 is used, for example, when performing autofocus, and receives a signal from a process unit that performs image processing on information on an image plane monitored by, for example, a CCD.

Next, embodiments of the invention of claim (2) will be explained.

In this embodiment, in a projection exposure apparatus similar to that shown in FIG. 1, the moving mechanism 60 is configured to move the reticle 20 and the projection lens 30 so as to substantially satisfy the above relationship (b). Specifically, the control unit 6 in FIG.
In the system area of the memory in 1, a program for calculating the above equations is stored in advance, and except for this point, the embodiment is almost the same as the embodiment of claim (1).

That is, in the state in which the object is in focus in FIG. 2, Bf holds true. However, f is the focal length of the projection lens 20.

When this equation (V) is differentiated with respect to B, the right-hand side becomes 0 since 1/f is constant in the focused state.

Regarding the first term on the left side, becomes.

Also, regarding the second term on the left side, becomes.

From these, (v) The differential of the expression is So, rearranging this, we get 2 dB=-dA 2 becomes.

Here, since B/A=M (M>O), dB=-
M” dA. Then, when ΔA and ΔB are minute amounts, d
Since it can be considered that A=ΔASdB=ΔB, (i>formula, (
(2) From the formula, Δ22 = M2 (ΔZ+ -Δ22), and rearranging this, ΔZ, = (1--)Δz2 2 , which is the same as the formula (b).

From the above, conversely, if ΔZ1 and Δz2 are moved so as to substantially satisfy the relationship of equation ('b), it is possible to change the magnification while keeping the image in focus.

In the apparatus of this embodiment, magnification adjustment can be performed as follows.

(2) Similarly to (2) in the above embodiment, the values of distance A and distance B are stored in the RAM, and the value of magnification M (B/A) is calculated and stored.

(2) Similarly to (2) in the above embodiment, for example, when the forward direction button 62 is pressed, a signal is sent to the control unit 61 to move the projection lens 30 a predetermined distance (ΔZ2) in the forward direction toward the light [10].

(2) The CPU calculates the value of Δz1 from the previously stored multiplier 1 and ΔZ2 input using the forward direction button 62 based on the above equation.

■ The signals corresponding to the above ΔZl and ΔZ2 are transmitted to the reticle position adjustment mechanism 40 and the projection lens position adjustment mechanism 50.
These move the reticle 20 and the projection lens 30 in the direction of the optical axis P. During this movement, the focus is maintained using equations (a) and (b) above.

■ Also, if you press the negative direction button 63, the projection lens 30
A signal to move the reticle 20 and the projection lens 30 by a predetermined distance (ΔZ2) in the negative direction is sent to the control unit 61, and the reticle 20 and the projection lens 30 are moved in the direction of the optical axis P in the same manner as described above.

■ In this way, the reticle 20 and the projection lens 30
When the image moves, the values of distance A and distance B change while remaining in focus, so it is possible to change the magnification M (B/A) without losing focus.

Note that the line human power 65 is used, for example, for autoscaling.

Next, other embodiments of the present invention will be described.

(1) The signal input manually to the control unit 61 is ΔZ, and the CPU
The one calculated by ΔZ2 may be used.

(2) The movement mechanism may be mechanically controlled by gears or the like instead of using combinator control.

For example, in the first embodiment, if the magnification of the projected image is 1x,
If the gear ratio is set so that when the reticle moves one time (ΔZ, = 1), the projection lens moves 1/2 (ΔZ2 = 1/2), the relationship in equation (a) above is satisfied, and the magnification remains constant. You can adjust the focus in this state.

In this case, although there is a disadvantage that the magnification cannot be changed freely, in a projection exposure apparatus in which there is little need to change the magnification, the structure is simple and it is advantageous in terms of cost.

(3) In reality, the system area of the memory in the control unit 61 shown in FIG. 1 often stores in advance a program that performs calculations of both the above equations (a) and (t).

In this case, which program to execute is selected depending on whether focus adjustment or magnification adjustment is performed.

〔Effect of the invention〕

According to the projection exposure apparatus of the present invention, since a moving mechanism is provided that moves the reticle and the projection lens so as to substantially satisfy the relationship expressed by equation (a), focusing can be performed while maintaining a constant magnification. .

According to another projection exposure apparatus of the present invention, since a moving mechanism is provided for moving the reticle and the projection lens so as to substantially satisfy the relationship of Equation (a), the magnification can be changed while the image is in focus.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the projection exposure apparatus of the embodiment, and FIG. 2 is an explanatory diagram of equations (a) and (b) in the embodiment. 10... Light source 20... Reticle 30
... Projection lens 30A... First principal plane 30
B... Second principal plane 40... Reticle position adjustment mechanism 50... Projection lens position adjustment mechanism 60... Movement mechanism 61... Control unit 62.
...Positive direction button 63...Negative direction button 64.
... Numerical human power section 71 ... Pellicle 81 ... Feed rollers 83, 84 ... Holding roller 65 ... Line human power F2 ... Microscope 82 ... Sprocket roller F ... Film

Claims (2)

[Claims] (1) A light source, a reticle that is irradiated with light from the light source,
In a projection exposure apparatus equipped with a projection lens that projects an image of a reticle, the reticle position adjustment mechanism adjusts the position by displacing the reticle in the optical axis direction, and the reticle position adjustment mechanism adjusts the position by displacing the projection lens in the optical axis direction. projection lens position adjustment mechanism, the amount of displacement of the reticle is ΔZ_1, and the amount of displacement of the projection lens is ΔZ_1.
Z_2, and when the magnification of the projected image of the reticle is M, ΔZ_1=(1+1/M)ΔZ_2...This means that a moving mechanism is provided to move the reticle and projection lens so as to substantially satisfy the relationship (a). Characteristic projection exposure equipment. (2) a light source and a reticle that is irradiated with light from the light source;
In a projection exposure apparatus equipped with a projection lens that projects an image of a reticle, the reticle position adjustment mechanism adjusts the position by displacing the reticle in the optical axis direction, and the reticle position adjustment mechanism adjusts the position by displacing the projection lens in the optical axis direction. projection lens position adjustment mechanism, the amount of displacement of the reticle is ΔZ_1, and the amount of displacement of the projection lens is ΔZ_1.
Z_2, and the magnification of the projected image of the reticle is M, then ΔZ_1=(1-1/M^2)ΔZ_2... A moving mechanism that moves the reticle and projection lens so as to almost satisfy the relationship (b). A projection exposure apparatus comprising: