JPH067544B2 - Sample positioning mechanism for double-sided aligner - Google Patents

Description

TECHNICAL FIELD The present invention relates to a positioning mechanism for simultaneously performing alignment and exposure on both sides of a sample, for example, in a manufacturing process of semiconductor elements, power ICs, crystal oscillators, etc. It is suitable for use.

(Prior Art) In a photolithography process in a semiconductor manufacturing process, a stage provided so as to be adjustable respectively in X-axis, Y-axis and Z-axis directions orthogonal to each other and in a θ-direction with respect to a tilt angle of the Z-axis is used. A sample made of a silicon single crystal plate or the like is fixed to a sample table placed thereon by suction means, and the stage is finely moved in the respective directions to align the sample with the mask pattern.

Since the sample can be used on both the front and back sides, the photolithography process is repeated twice for one sample, so that the resist film coating, alignment, pre-baking, development and other processes are also repeated.

(Technical problem) Attempts to simplify the photolithography process have been made in the past, and a method of performing simultaneous double-sided exposure only for primary exposure (the step of inserting alignment marks etc.) that does not require precise alignment has already been implemented. However, that alone does not provide a drastic solution, and the complex process must be repeated.

On the other hand, some devices were capable of aligning and exposing both upper and lower surfaces simultaneously. The apparatus has a mechanism for performing alignment when the sample is inserted between the upper and lower masks by a transfer hand that transfers the sample, and the sample is held by the hand that also serves as a stage without contacting the lower mask and the upper mask. Therefore, there is always a possibility that the sample will be displaced when the hand is opened or the mask is brought into close contact after alignment. This is an unavoidable drawback as long as there is no means to keep the sample fixed before and after alignment. Also, since the hand stage is large in this device, the amount of movement of the upper and lower masks also increases,
There is also a problem that the positional deviation easily occurs.

The present invention solves the above-mentioned drawbacks and problems, and an object thereof is to be able to hold and fix a sample between upper and lower mask patterns by a pair of supporting claws. Can be done at the same time,
Further, it is another object of the present invention to provide a sample positioning mechanism for a double-sided aligner, which avoids duplication of resist film coating, prebag, development, and other related processes, and contributes to speeding up of the manufacturing cycle and reduction of manufacturing cost.

(Technical Means) The purpose is to provide a stage body 3 having a window hole 1 penetrating vertically and having a lower mask 2 on which a sample S for placing the sample S is arranged.
And an end having a curved cross-section that is arranged so as to cross the window along the X direction or the Y direction orthogonal to the X direction, and that supports the sample by abutting the edges of the sample on the lower mask by their respective tips. A pair of sample supporting claws 6 and 7 having parts 4 and 5, and mounting members 8 and 9 provided on the stage body and mounted with the sample supporting claws.
Can be reached by means of an adjusting means for moving in the X and Y directions and rotating on the XY plane.

(Example) Hereinafter, description will be given with reference to the drawings. A sample positioning mechanism for a double-sided aligner according to the present invention is illustrated in FIG. 1, which is related to the manufacture of a semiconductor device, and is incorporated in an exposure unit set in a central portion of a semiconductor device manufacturing apparatus described later. .

The stage body 3 is configured to be finely movable in the θ direction with respect to the X, Y, and Z axis directions and the inclination of the Z axis, and as a means for the adjustment in the θ direction, for example, a spherical seat portion.
It is supported by 11A or a flexible support plate 11B. A window hole 1 is formed in the center of the main body so as to pass through it vertically, and a peripheral portion of the window on the upper side of the main body has a lower mask 2 on which a sample S is placed.
It is the mounting surface 12 of. Reference numeral 13 is a circumferential groove provided on the mounting surface 12 so as to surround the window hole 1, and includes a suction passage 14 in the main body and a connector 15
Through to the suction device. 16 ₁ , 16 ₂ and 16 ₃ are lower masks 2
Shows the positioning pin of. The lower mask 2 is transparent and has good accuracy on both sides, and has a ruled line or the like on one side or is plain, and glass products can be used as in the conventional case.

The wafer, that is, the sample S is placed on the lower mask, and a pair of sample support claws 6 and 7 are brought into contact with the edges of the sample S from the left and right to fix the wafer S by clamping (see FIGS. 8 to 10). .
The claws 6 and 7 themselves are formed of a material having a spring property having a material thickness smaller than that of the sample S, and the tips thereof are curved sections or bent sections in the Z-axis direction. Has become. Although the thickness of the outer upper nail tip may exceed the thickness of the sample due to the formation of the curved end portions 4 and 5, when pressed by the upper mask pattern, it is easily flattened to the thickness of the sample. The shapes of the curved ends 4 and 5 are illustrated in FIGS. 4 (a), (b) and (c). The figure (a) is a curved shape consisting of an arc opened upwards,
The figure (b) shows a wavy curve in which a downward arc is connected to the left and right of an upward arc, and the figure (c) shows a sawtooth-shaped bent end in which three V-shapes are continuous. Such pawls 6 and 7 can be formed of stainless steel, spring steel, phosphor bronze or the like. 17 ₁ , 17
₂ ... is a small hole provided in each claw, such as 3 inches, 2 inches, etc., prepared for changing the mounting device according to the size of the wafer,
It is fixed to the mounting members 8 and 9 by means of stoppers 18 and 19, respectively.

Since the mounting members 8 and 9 are members that fix the base ends of the claws that sandwich the sample S from the left and right, they are arranged on the left and right of the sample mounting surface 12, and the outer peripheral portion 20 of the stage body 3 in which the sample mounting surface 12 is provided is Member 8,
It has a step shape with a thickness of about 9 lower. The first mounting member 8 to which the first supporting claw 6 located on the left side when viewed from the operation portion side is fixed extends in the Y-axis direction, and the mounting surface 12 is surrounded from the operation portion side end portion. It is formed in a hook shape integrally having an angle member 21 extending in the X direction. The mounting member 8 can be moved integrally with the outer frame 22 in the X-axis direction to the portion in the Y-axis direction of the angled outer frame 22 arranged on the outer side (left side) thereof, and can be moved in the Y-axis direction. A flexible plate in the X-axis direction so that only the first mounting member 8 can be independently moved by the bending of the flexible plates 23 and 24.
It is attached via 23 and 24.

25 is a Y operation shaft that presses the first mounting member 8 in the Y axis direction,
The main body 3 has a tip portion 25a having a screw which is screwed with a mounting base 26 provided on the side of the operation portion side. 27 is a return spring,
It is provided between the first mounting member 8 and the outer frame 22 so as to pressurize the first mounting member 8 toward the Y-direction operating portion.

A link 28 for moving the frame 22 and the first mounting member 8 in the X-axis direction is attached to the end of the outer frame 22 on the side of the operation portion,
Since the link 28 extends in the X-axis direction, the Y operation shaft
Similar to 25, the X operation shaft 30 is arranged in the Y axis direction so as to facilitate the operation, the crank 29 is connected to convert the forward / backward movement of the tip of the shaft 30 into the movement in the X axis direction. 29a is a crank support shaft,
Reference numeral 30a denotes a tip end portion having a screw to be screwed with the mounting base 31 provided on the end side of the main body 3 on the operation portion side. The outer frame 22 integrally has an outer angle 32 extending in the X-axis direction on the side opposite to the mounting surface 12, and is provided on both left and right ends of the angle and is a flexible plate in the Y-axis direction.
It is attached to the main body 3 via 33 and 34. Reference numeral 35 is a return spring, which is provided between the outer angle 32 and the main body so as to press the angle 32 to the opposite side in the X direction.

The two members in the X-axis direction, that is, the angle member 21 and the outer angle 32, are connected to the second mounting member 8 parallel to the first mounting member 8 at their ends. The member 9 has the above-mentioned supporting claws 6,
The other of 7, i.e., the second claw 7, is attached, but the second attachment member 9 has a long hole 3 in the same direction so as to be movable in the Y-axis direction.
6 and 37 are linked to the angle member 21 and the outer angle 32. Reference numerals 38 and 39 denote connecting shafts fixed to the angle member 21 and the outer angle 32 through the long holes 36 and 37, respectively.
There is no play in the X-axis direction between 38 and 39 and long holes 36 and 37,
Moreover, the second mounting member 9 is springed toward the angle member 21.
It is urged toward the operation portion side in the Y direction by 43. φ operation axis 40
Is provided to press the second mounting member 9 in the Y-axis direction against the return spring 43.
The movement of the mounting member 9 rotates the sample in the φ direction about the end 4 of the first claw 6. The φ operation shaft 40 is screwed with a mounting portion 41 provided on the angle member 21 of the first mounting member 8 to form a shaft tip portion.
40a abuts on a receiving portion 42 provided on the second mounting member 9. 44
Is a push plate, and the second mounting member 9
It is fixed to the angle member 21 so as to apply pressure in the direction.

A semiconductor manufacturing apparatus 50 in which the sample positioning mechanism 10 having the above structure is incorporated is shown in FIGS. 51 in each figure
Is a working unit on the upper surface of the apparatus main body, 52 is an exposure unit at the center of the working unit, 53 is a sample supply side elevator arranged on the right side of the working unit, 54 is detection of an orientation flat unit arranged between the elevator 53 and the exposure unit 52 , A pre-alignment unit having a direction and centering mechanism, 55 is a loading means such as a pusher for sending the sample from the elevator 53 to the pre-alignment unit 54, 56
Is a transporting means such as a mechanical hand for sending the sample from the pre-alignment unit 54 to the lower mask 2, 57 is a similar transporting means on the unloading side, 58 is a unloading means such as a pusher, and 59 is a storage side elevator. 60 is an alignment microscope on the exposure unit 52,
61 is an upper mask holder on the upper stage, 62 is a lower mask holder on the same stage, 63 is an upper lamp house, 64 is a lower lamp house,
Reference numeral 65 is a control device, and 66 and 67 are lamp power supply control units. Further, in FIG. 3, 70 is a mounting plate provided on the vertically movable mechanism, 71 is a cross roller bearing of a rotation guide, 72 is a lower exposure cylinder,
73 is an upper lower mask, 74 is a Y-axis ball roller guide, 75
Is a fine movement knob for the Y axis, 76 is a fine movement table for the X axis, 77 is a fine movement knob for the X axis, and 78 is a lower substrate, on which an XY lower mask consisting of upper, middle and lower lower masks is placed.

(Operation) The mechanism of the present invention configured as described above enables simultaneous alignment on both surfaces of the sample. The sample is pre-aligned by the pre-alignment unit 54 on the carry-in side, and then carried on the upper surface of the lower central mask 2 by the carry-in means 55. At this time, since the sample S is supported by the first and second supporting claws 6 and 7, the second mounting member 9 can be slightly opened outward (to the right in FIG. 1) against the push plate 44, As a result, the curved end portions 4 and 5 of the tip of the nail hit the edge of the sample and can be held and fixed from the left and right.

In this state, the upper mask holder 61 is lowered toward the sample S until the upper mask 2'contacts or does not contact the sample. It is assumed that the lower mask holder 62 on which the lower mask 2 is placed is at a predetermined position on the lower surface of the lower mask 2, and the upper and lower mask holders 61 and 62 are held at pre-aligned positions. Observation with a microscope 60 is performed here, and the mask patterns 83 and 84 formed on the upper and lower masks 2'and the sample S
Align the alignment marks 85 and 86 of (see FIG. 2). At that time, the sample S is slightly moved, but in the movements in the X-axis and Y-axis directions, when the X operation shaft 31 and the Y operation shaft 25 are operated, the pair of supporting claws 6 and 7 are integrally moved in the X axis direction and the Y axis direction. Moving. If it is necessary to rotate the sample about the first supporting claw end 4 in the φ direction, the φ operation shaft is operated (FIG. 8). Of course,
Similarly to the second supporting claw 7, the first supporting claw 6 can be movable in the Y-axis reverse direction (FIG. 9). For square samples, the curved ends 4 and 5 of the support claws 6 and 7 are planarly arcuate to facilitate rotation in the φ direction (see FIGS. 8 to 8). (See Figure 10).

When the alignment is completed, exposure is performed with the upper and lower masks 2 ', 2 in close contact with the sample S (parallel alignment is assumed to be completed in advance). After that, the supporting claws 6 and 7 are separated from the sample S. Next, the upper mask holder 61 rises and the carry-out means 57 carries out the carry-out, and the carry-out means 58 relays and the sample is stored in the carrier of the storage-side elevator 59.

(Effect) Therefore, according to the present invention, in aligning the sample between the upper and lower mask patterns, the pair of supporting claws 6 and 7 are used.
Since the process proceeds while it is fixed on the substrate, the positional relationship between the sample and the mask pattern is fixed through alignment and exposure.
Since it is easy to complete the steps such as exposure and perform related resist film coating, pre-baking, development and other steps on both sides, speeding up the manufacturing cycle is realized and it also contributes to reducing manufacturing costs. It has a significant effect in practice such as being large.

[Brief description of drawings]

The drawings show an embodiment of the mechanism of the present invention. FIG. 1 is a plan view, FIG. 2 is a cross-sectional view schematically showing a main portion, and FIG. Figures (a), (b), (c)
Are sectional views of three kinds of curved end portions, FIG. 5 is a front view of a semiconductor device manufacturing apparatus incorporating the mechanism of the present invention, FIG. 6 is a side view, FIG. 7 is an explanatory plan view, FIG. 8 and FIG. FIG. 10 and FIG. 10 are explanatory views of the operation.

Claims (3)

[Claims] 1. A stage main body 3 having a window hole 1 penetrating vertically and having a lower mask 2 for placing a sample S on the upper surface thereof.
And an end having a curved cross-section that is arranged so as to cross the window along the X direction or the Y direction orthogonal to the X direction, and that supports the sample by abutting the edges of the sample on the lower mask by their respective tips. A pair of sample supporting claws 6 and 7 having parts 4 and 5, and mounting members 8 and 9 provided on the stage body and mounted with the sample supporting claws.
A sample positioning mechanism for a double-sided aligner, which comprises an adjusting means for moving the X-axis in the X and Y directions and rotating the X-axis in the XY plane. 2. The mounting members 8 and 9 to which the sample supporting claws are mounted are arranged on both left and right sides of the window hole 1 in the Y direction, and the first mounting member 8 and the second mounting member 9 are provided. Are independently movable in the Y direction, and the angle member is sandwiched through the window hole 1 toward the front and rear sides in the X direction.
21 and angle 22 are arranged, both angles 21, 22
2. The sample positioning mechanism for a double-sided aligner according to claim 1, further comprising adjusting means configured such that the first and second mounting members 8 and 9 are integrally movably connected in the X direction. 3. The first and second mounting members 8 and 9 are independently Y-shaped.
Y operation axis 25 to be operated in the direction of rotation, φ to be operated around the Z axis
X that integrally operates the operation shaft 40 and both members 8 and 9 in the X direction
The sample positioning mechanism for a double-sided aligner according to claim 1, wherein the operation shaft 30 is provided on the operation side of the main body.