JP2008041874A - Thick-film resist water process and its apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To faithfully and sharply reproduce a circuit pattern of an exposing mask. <P>SOLUTION: The thick-film resist process coats the surface of a silicon substrate (S) with a resist (L), exposes the resist (L) to a circuit forming pattern to print the pattern thereto, and develops the resist (L) printed with the circuit pattern. The resist (L) is exposed after giving a water content to the resist (L), thereby indeneketen is quickly and massively formed by the water content of the resist (L), and the indenketene is changed to indenecarbonate soluble to an alkali developing solution due to the water content of the resist (L), thus achieving extremely faithful exposure/development on an exposing mask (M). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thick film resist water process and apparatus capable of sharper development.

  In the semiconductor manufacturing process, a photoresist is uniformly applied and baked on the surface of a silicon substrate on which a semiconductor circuit is formed, and a semiconductor manufacturing mask on which a circuit pattern is formed is placed thereon, and then the top of the mask is applied. After exposure, the circuit pattern is baked onto the resist layer, and after that, the circuit pattern part changed (or not changed) by the chemical reaction by the exposure is removed with a developer, and finally the part removed by development is removed. A series of steps of removing the matching part by development and further forming an insulating film, a conductive film or other necessary film thereon are repeated, and a predetermined semiconductor circuit is formed on the surface of the silicon substrate. Is. As an apparatus for such a thick film resist process, there is an invention such as Japanese Patent Application Laid-Open No. 2000-277420.

  However, in recent years, micro-machines that show further miniaturization of semiconductor circuits and new developments, hard disks that require higher capacity, and IC chip stacks as electronic devices become more sophisticated. With respect to thick film resists for forming IC bumps, which are indispensable for structure formation and are now in the spotlight, higher resolution is required for further enhancement of performance. First, the conventional exposure / development state will be described with reference to FIGS. 15A and 15B, and the problems will be highlighted.

  FIG. 15A shows an exposure mask (M) placed in close contact with or in close proximity to a silicon substrate (S) coated with a resist (L), and a light beam having a predetermined wavelength from above the exposure mask (M). Is exposed and the circuit pattern formed on the exposure mask (M) is burned onto the resist (L). FIG. 15 (b1) shows a state in which the resist portion that coincides with the transparent portion (d) of the circuit pattern undergoes a chemical reaction upon exposure, and a substance (indenecarboxylic acid) that is soluble in an alkaline developer is generated in the portion. Show. In the case of the conventional example, the light transmittance with respect to the resist in the exposed portion hardly changes until about 100 seconds from the start of exposure, and then the transmittance increases, reaches a peak in about 500 seconds, and then starts decreasing. During this time, the change in transmittance (the amount of indenecarboxylic acid produced) is gentle and the sensitivity is low. As a result, as shown in FIG. 15 (b1), the boundary (Kb) between the photosensitive part (Rb) and the non-photosensitive part (HRb) due to exposure is inclined, and the closer to the silicon substrate (S) side, the more the photosensitive part (Rb) becomes. The width becomes narrower.

  In FIG. 15 (b2), since this is developed using a developer, the boundary (Kb) between the photosensitive portion (Rb) and the non-photosensitive portion (HRb) is inclined as described above. In S), the angle of the side wall (LS) of the residual resist (L ′) remaining on the surface increases. In some cases, unremoved resist (Lz) is generated at the bottom of the residual resist (L ′).

FIG. 15 (a3, b3) shows the developed part (E1, E2) between the remaining resist (L ′) or (L ′ + Lz) in the case of developing the figure (a2, b2). In this case, the dimension (E2w) of the developed part (groove or hole) is much narrower than the width (dw) of the light-transmitting part (d) of the original mask (M), so that the resolution is deteriorated, in other words, There has been a problem that the width (dw) of the translucent portion (d) of the mask (M) which is the required line width cannot be obtained, and the required high resolution cannot be obtained at all.
JP 2000-277420 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to develop a thick film resist water process and apparatus capable of faithfully and sharply reproducing a circuit pattern of an exposure mask. .

  The thick film resist water process described in claim 1 is the following: “The resist (L) is applied to the surface of the silicon substrate (S), the circuit formation pattern is exposed to the resist (L), and the circuit formation pattern is baked. Then, a thick film resist process for developing the resist (L) onto which the circuit formation pattern has been baked, and after exposing the resist (L) to moisture before exposure, the resist (L) is exposed. '' Features.

The invention according to claim 2 is an apparatus (A) for carrying out the water process according to claim 1,
(a) a cassette unit (1) for supplying or containing a silicon substrate (S);
(b) A mobile robot hand (2) for taking out and transferring the silicon substrate (S) from the cassette unit (1) or returning the treated silicon substrate (S) to the cassette unit (1);
(c) a coating unit (4) for applying a resist (L) to the surface of the silicon substrate (S) taken out;
(d) a moisture treatment unit (6) for applying moisture to the resist (L) of the coated silicon substrate (S) and drying it; and
(e) After moisture application, an exposure unit (7) that exposes the circuit formation pattern on the resist (L) surface of the dried silicon substrate (S) and prints the circuit formation pattern;
and (f) a development unit (8) for developing the resist (L) of the silicon substrate (S) on which the circuit formation pattern is baked.

Claim 3 relates to a moisture treatment unit (6) used in the thick film resist water process apparatus (A) of claim 2,
"The moisture treatment unit (6)
(h) a chamber (60) for storing a silicon substrate;
(i) an opening shutter (61) provided in the chamber (60) and enabling the silicon substrate (S) to enter and exit from the receiving shelf (66);
(j) a receiving shelf (66) that is erected in the chamber (60) and has a plurality of rows of receiving steps (65) for the silicon substrate (S);
(k) a moisture supply nozzle (68) for supplying moisture to the silicon substrate (S) in the chamber (60);
(l) In a state where the silicon substrate (S) is housed in the chamber (60), a vacuum pipe (60c) for evacuating the chamber (60) before and after applying the moisture supply,
(m) It is composed of a tilting mechanism (69) that tilts the receiving shelf (66) when supplying moisture.
It is comprised of "."

  By supplying moisture to the resist (L) before exposure, indenecarboxylic acid is formed inside the resist (L), and it is possible to achieve higher resolution and higher aspect in the thick film resist process by the mechanism described below. did it. Based on this fact, the moisture treatment unit (6) is installed in front of the exposure unit (7), so the photosensitivity can be greatly improved, and as a result, the subsequent development unit (8) We were able to greatly improve the resolution by development. The moisture treatment unit (6) has a tilting mechanism (69) that tilts the receiving shelf (66) when supplying moisture, so that water accumulated on the surface of the resist (L) immediately flows down to the surface. The water content of the entire resist (L) is kept uniform without accumulating.

  FIG. 1 is a plan view of the device (A) of the present invention. The device (A) of the present invention comprises a cassette unit (1), a mobile robot hand (2), a centering unit (3), a coating unit (4), a heating / cooling unit (5), a moisture treatment unit (6), an exposure unit. The unit (7), the developing unit (8), the housing (9), and the accessory equipment (91) are included. As can be seen from FIG. 1, the arrangement of each unit is arranged before and after the exposure unit (7) provided at the left end in the figure, and the mobile robot hand (2) runs between the front and rear units. The silicon substrate (S) is handled. As the accessory part (91), there are a chemical solution box (91a), a power supply box (91b), a vacuum pump box (91c), and a piping system, an electrical system, a control system, etc. for connecting these units.

  The cassette unit (1) for supplying or containing the silicon substrate (S) is installed in a row at the right end on the front side of the device (A) of the present invention. In this embodiment, the cassette unit (1) includes a supply cassette unit (1A) and an extraction cassette unit (1B), and a cassette (11) having the same structure can be mounted. In this embodiment, two supply cassette units (1A) are provided on the right side, and one take-out cassette unit (1B) is provided on the side. Of course, the number of cassette units (1) to be installed is appropriately selected depending on the processing capacity.

  The cassette (11) is compatible with both supply and removal, and at least one side surface is open [in the case of FIG. 2, the front surface (set so that the mobile robot hand (2) side is open)], its It has a vertically long cylindrical shape with the opening portion serving as the entrance / exit (15) of the silicon substrate (S), and receiving steps (16) for accommodating the silicon substrate (S) are formed at regular intervals on the inner wall thereof. In addition, in a state where a large number of silicon substrates (S) are accommodated, it can be transferred between the processing apparatuses such as the processing apparatus at the previous stage and the processing apparatus at the subsequent stage of the apparatus (A) of the present invention. 2, in order to avoid complication of the drawing, the step (16) is indicated by a one-dot chain line and the silicon substrate (S) is omitted. 11a) and the latter as (11b).

  The structure of the cassette unit (1) using such a cassette (11) is that the mobile robot hand (2) moves up and down in the vertical direction in the case of the present embodiment. 1D), but when the cassette unit (1) itself is moved up and down, although not shown, the holding body is provided with an up-down direction pitch feed mechanism and mounted on a pedestal provided in the up-down direction pitch feed mechanism. The placed cassette unit (1) may be pitch-fed so as to move in the up-and-down direction.

  The mobile robot hand (2) is as shown in FIG. 14. The silicon substrate (S) is taken out from the cassette (11) and transferred to the next process unit, or the processed silicon substrate (S) is transferred to the cassette unit. For returning to (1) or for loading / unloading the silicon substrate (S) into / from each processing unit, a traveling unit (21) that travels along the cassette unit (1) and other processing units, and its Elevating mechanism (23) installed on the upper side [generally, a linear guide, a ball screw, and a stepping motor that are erected on the Z axis (elevating direction). And an articulated arm (22) in which the arm (22a) is combined with the link mechanism and the servo or stepping motor (22b) is set in the joint part, and the tip part of the articulated arm (22). And a silicon substrate handling hand (24) provided. In the case of the present embodiment, the hand (24) has a bifurcated tip tweezers (25), and this tip tweezers (25) is normally detachable by vacuum suction and normal pressure, and is a silicon substrate (S ) Is adsorbed (or removed) at a predetermined position. The travel section (21) is generally traveled by a feeding device that combines a linear guide (21a) provided between unit rows, a ball screw (not shown), and a stepping motor (not shown). To do.

  The centering unit (3) is as shown in FIG. 7, and the silicon substrate (S) transported by the mobile robot hand (20) coincides with the center of each unit (or the unit following the centering unit (3)). It is equipped with a silicon substrate (S) suction stage (31) and a centering sensor (32), and the suction stage (31) rotates and rotates in one direction (in this embodiment, front and back). Direction). The centering sensor (32) rotates the silicon substrate (S) adsorbed on the adsorption stage (31), measures the amount of movement (Δ) of the edge of the silicon substrate (S) at that time, and determines the amount of displacement (Δ ) Stops the suction stage (31) and then moves half of the displacement (Δ) in the front-rear direction to move the center of the centering unit (3) and the center of the silicon substrate (S). (Thus, the center of the silicon substrate (S) and the center of the suction stage (31) are usually slightly shifted). After the positioning is completed, it is transferred to the next process by the mobile robot hand (2).

  The coating unit (4) [FIGS. 3 to 6] is a unit for uniformly coating the resist (L) uniformly on the entire surface of the silicon substrate (S), and the resist supply nozzle (41) and the subordinate silicon for that purpose. Resist pool (L1) [resist (L) is spin-coated on the surface periphery of the substrate (S) == Liquid resist (L) is dropped on the surface of the silicon substrate (S), and then the silicon substrate (S) is Phenomenon that resist (L) accumulates thicker from the inside on the peripheral edge of the silicon substrate (S) due to its surface tension when rotating and spreading the resist (L) in the peripheral direction by the centrifugal force '' ], A resist pool removing nozzle (42) for removing the back surface and a back surface cleaning nozzle (43) for removing dirt on the back surface of the silicon substrate (S). In this embodiment, it is installed on the opposite side (the back side of the apparatus) of the cassette unit (1) beyond the mobile robot hand (20).

  The main body mechanism of the coating unit (4) is to adsorb the silicon substrate (S) and rotate it around its center as a spin chuck (44), a drive motor (45) to rotate the spin chuck (44), An upper cover (47) in which the opening (46) through which the silicon substrate (S) enters and exits opens on the ceiling surface, a lower cover (48) for receiving liquid droplets, and upper and lower covers (47) (48) are attached, A base (49) that moves up and down together with the upper and lower covers (47) and (48), a lifting cylinder (49a) that is mounted on the base (49) and lifts the base (49), and a lifting guide that serves as a guide during the lifting ( 49b). A drainage groove (49c) into which a drainage gap formed by the peripheral edge portions of the upper and lower covers (47) (48) is fitted is formed at the peripheral edge portion of the base (49), and a drain pipe (not shown) It is connected to the.

  The back cleaning nozzle (43) protrudes upward through the tray (48a) provided in the center of the lower cover (48), and the main body (43a) of the back cleaning nozzle (43) is attached to the base (49). And is raised and lowered together with the base (49). The spin chuck (44) attached to the drive motor (45) is independent from the base (49) and only rotates. Therefore, the through hole (48b) provided in the lower cover (48) is fitted in the spin chuck shaft (44a) in a watertight manner, and the lower cover (48) is moved up and down while maintaining the watertight state. It has become. The drive shaft (45a) of the drive motor (45) is attached to the spin chuck shaft (44a). Although not shown, the spin chuck shaft (44a) incorporates a vacuum piping mechanism for a vacuum chuck.

  Further, the opening (46) of the upper cover (47) is opened and closed by an elevating lid (10) disposed above, and the elevating lid (10) is provided on the lid elevating cylinder (10a). It is attached to the cylinder rod (10c) with a lid mounting arm (10b).

  The resist supply nozzle (41) is attached to the swing / lift cylinder (41b) via the swing arm (41a). The cylinder (41b) includes an elevating part (41c) and a swing part (41d), and the swing arm (41a) is attached to a cylinder rod (41e) of the cylinder (41b).

  The resist pool removing nozzle (42) of the resist pool removing section (42A) is installed at the tip of the horizontal extendable arm (42a), and the tip of the resist pool removing nozzle (42) is silicon at the peripheral edge of the silicon substrate (S). It faces the outside of the substrate (S), and the supplied pure water is sprayed to the peripheral edge of the silicon substrate (S).

  The resist pool removal nozzle (42) horizontally moves in accordance with the horizontal expansion and contraction of the extendable arm (42a), and includes a supply nozzle lifting cylinder (not shown) and a supply nozzle lifting linear guide (not shown). It is raised and lowered by the supply nozzle raising / lowering part (42c). Note that the resist pool removing nozzle (42) is surrounded by a nozzle cover (42f) having an open bottom so that the pure water is not scattered particularly inside the silicon substrate (S). In addition, the resist pool removing portion (42A) composed of the above-mentioned members is installed on the base (42h), and the resist pool removing nozzle (42) that has returned to the home position is a water receiver ( 42i) receives pure water (dropped or spilled water) from the resist pool removing nozzle (42). A drain pipe (42j) is installed at the bottom of the water receiver (42i). A pure water supply pipe (not shown) is connected to the resist pool removing nozzle (42).

  The heating / cooling unit (5) includes a heating unit part (50) and a cooling unit part (59), which are stacked one above the other. The heating unit section (50) and the cooling unit section (59) are the same except for the heating plate (51) for the silicon substrate (S) and the cooling plate (58). Therefore, the description of the cooling unit (59) is replaced by the description of the heating unit (50). The same number is attached | subjected to the member of the same function.

  The heating unit (50) heats the silicon substrate (S) and dries the resist (L) applied on the surface (in contrast, the cooling unit (59) is the heating unit (50). This is for cooling the heat-dried silicon substrate (S).), A front / rear opening (53) is provided on the front surface of the rectangular box-shaped main body (52), and the front / rear opening (53) is provided on the front surface thereof. An opening / closing door (52a) is provided for opening and closing the door in an airtight manner. And the side of the vacuum exhaust pipe (55) connected to the main body (52) is connected to the side, and the inside of the main body (52) can be switched to the vacuum / atmospheric pressure state by switching the valve. ing.

  A heating plate (51) [a cooling plate (58) in the case of the cooling unit section (59)] is installed inside the main body (52), and a horizontal lifting plate (56) is installed below the heating plate (51) so as to be movable up and down. The horizontal elevating plate (56) is provided with three support rods (54) for supporting the silicon substrate (S), and a vertical elevating guide is made by the guide rod (56a). . A support rod lifting motor (59m) is provided on the back of the main body (52), and a support rod lifting arm (57a) is attached to its drive shaft (59a) so that it can swing up and down. Rollers (57) that support both sides of the lifting plate (56) from below are provided. Thermocouples (51a) and (58a) are respectively installed on the heating plate (51) and the cooling plate (58).

  In this embodiment, three moisture treatment units (6) are installed beside the centering unit (3) (the number of installation units is naturally changed depending on the processing capacity of the apparatus), and they are used in batch mode. It has come to be. The chamber (60) of the moisture treatment unit (6) has a cylindrical shape and is provided with an entrance / exit opening (60a) in front of it, and an opening shutter (61) is open / air-tightly closed in front of the entrance / exit opening (60a). It is provided so that it can be opened and closed by a door opening / closing cylinder (61a). The inner bottom of the chamber (60) is tapered toward the center, and a drain pipe (60b) is provided at the center of the inner bottom. Further, a vacuum pipe (60c), an inert gas supply pipe (60d), and a pure water supply pipe (60e) are installed on the side surface and the bottom surface.

  Further, a tilting shaft (62) is disposed between the lower side surfaces of the chamber (60) so as to be tiltable, and a tilting motor (63m) [a tilting cylinder or a solenoid rotating at a certain angle may be used. ] Via a coupling (63a). Further, in the chamber (60), a tilting base (64) is installed on the tilting shaft (62), and a receiving shelf (66) comprising a set of four is set up on the tilting base (64). A plurality of rows of receiving steps (65) for the silicon substrate (S) are formed on the inner surface. The distance between the two receiving shelves (66) standing on the entrance / exit opening (60a) side is set to such a width that the silicon substrate (S) can be taken into and out of the receiving stage (65) between them. Yes. As shown in FIG. 12, the tilting axis of the tilting shaft (62) is provided such that the receiving shelf (66) falls to the back side when moisture is sprayed.

  Further, a moisture supply nozzle (68) for supplying moisture (in this case pure water) from the periphery of the silicon substrate (S) to the silicon substrate (S) to the outside of the receiving shelf (66) is provided in the chamber (60). Are installed at predetermined intervals on a pillar (68a) erected from the peripheral edge of the bottom.

  The exposure unit (7) is composed of a unit main body (71) and a silicon substrate transfer stage (70), and a silicon substrate transfer stage (70) is provided outside the entrance portion of the unit main body (71). The silicon substrate (S) supplied from the mobile robot hand (2) is temporarily held for delivery.

  The unit body (71) is composed of a fixed robot hand (72), an exposure unit (73), an exposure centering unit (74), a buffer unit (75), and a silicon substrate insertion / removal unit (76). The fixed robot hand (72) is provided adjacent to the substrate transfer stage (70). Like the mobile robot hand (2), the fixed robot hand (72) includes a multi-joint arm (72a) in which a plurality of arms are connected to bendable, and a control motor (72b) that controls the bending angle of the joint portion. In addition to the control motor (72b), the elevating drive unit (72c) for elevating the articulated arm (72a) and the rotating mechanism unit (72d) for rotating the elevating drive unit (72c) by 360 ° are configured.

  The exposure unit (73) burns the mask pattern onto the resist (L) applied to the surface of the silicon substrate (S), which is accurately positioned using ultraviolet rays or other short-wavelength light, as the circuit pattern of the integrated circuit. belongs to. The silicon substrate insertion / removal unit (76) is installed between the exposure unit (73) and the fixed robot hand (72), and receives the silicon substrate (S) received from the fixed robot hand (72). It is an apparatus for taking out the exposed silicon substrate (S) from the exposure unit (73) after being transferred into the exposure unit (73) and exposed. The exposure centering unit (74) is an apparatus for centering the silicon substrate (S) immediately before being fed into the exposure unit (73) and accurately aligning the θ direction. I will omit it.

  The buffer unit (75) is installed on the opposite side of the exposure centering unit (74) beyond the fixed robot hand (72), and stores the exposed or unexposed silicon substrate (S) in a stack. Is for. If the exposure cycle and the cycle of the pre-exposure process or the post-exposure process match, the buffer unit (75) is not necessarily required.

  The developing unit (8) shown in FIG. 13 includes a silicon substrate chucking mechanism (8A), a casing mechanism (8B), a developer supply mechanism (8C), and a pure water supply mechanism (8D). The spin chuck (80) of the silicon substrate chucking mechanism (8A), like the spin chuck described above, rotates the silicon substrate (S) after vacuum chucking and is connected by a rotary motor (81). . In this case, the silicon substrate (S) has been exposed. In addition, a vacuum piping mechanism is built in the rotation shaft (80a) of the spin chuck (80), and the silicon substrate (S) is adsorbed by the adsorption holes (80c) formed on the surface of the spin chuck table (80b). It can be fixed and rotated in that state.

  The casing mechanism (8B) is provided on an elevating / lowering cover (82) covering the lower side of the spin chuck (80), an elevating upper cover (83) covering the periphery of the spin chuck (80), and an elevating upper cover (83). The hood (83c), the hood (83c), and an elevating cylinder (not shown) for elevating and lowering the upper and lower / upper covers (82) and (83) independently. The rotating / lowering cover (82) has a rotating shaft (80a) of the spin chuck (80) inserted through the center thereof, and is moved up and down independently of the spin chuck (80). Further, the upper surface is gently inclined downward toward the outside, the outer peripheral portion thereof becomes a waste liquid discharge groove (82a), and the outer peripheral edge portion rises to become the outer wall portion (82b). A lower cover elevating bar (82c) is suspended from the lower surface of the elevating / lowering cover (82), and the elevating / lowering cover (82) is moved up and down by the elevating cylinder.

  The elevating upper cover (83) has a substantially cylindrical shape with an upper and lower opening, and is positioned so as to surround the side of the spin chuck (80) when lowered, and is liquid swung off by the centrifugal force from the rotating silicon substrate (S). Acts as a splash prevention wall. The elevating upper cover (83) is attached to the upper cover elevating bar (83a), and is raised and lowered by the elevating cylinder via the upper cover elevating bar (83a), and when it is at the lowest point, An exhaust passage (82d) is constituted by the elevating / lowering cover (82) positioned at the uppermost point.

  The hood (83c) has a cylindrical shape, and is equipped with a filter (not shown) for filtering downflow air passing through the hood (83c) so that it can be lifted and lowered independently. ing.

  The developer supply mechanism (8C) and the pure water supply mechanism (8D) are the same mechanism except for the materials supplied, such as developer and pure water. The description is applied to the pure water supply mechanism (8D), and the description is omitted. The arm attachment shaft (86a) of the developer supply mechanism (8C) is erected on the side of the spin chuck (80), and its lower end is attached to a swing motor (86m) that swings the arm attachment shaft (86a). A swing arm (86b) is attached to the upper end of the silicon substrate (S) that is attracted and fixed to the spin chuck (80). A hanging arm (85) is suspended from the tip of the swing arm (86b), and a developer supply nozzle (84a) is mounted on the hanging arm (85) (therefore, this is a pure water supply mechanism). In the case of (8D), the pure water supply nozzle (84b) is attached.)

  Next, the processing flow by the device (A) of the present invention will be described. First, the supply cassette (11a) [two in this case] filled with the silicon substrate (S) before processing is set on the base (1D) of the cassette unit (1A) on the supply side for empty storage. Set the cassette (11b) on the base (1D) of the cassette unit (1B) on the take-out side. Next, the movable robot hand (2) is operated, and one silicon substrate (S) is taken out from one of the supply cassettes (11a), and is moved to the front of the centering unit (3) in that state. The height of the silicon substrate handling hand (24), the height of the silicon substrate (S) stored in the supply cassette (11a), the suction stage (31) of the centering unit (3), and other devices (A) Needless to say, when the height of the silicon substrate processing stage of each unit is different, the height is naturally adjusted by the lifting mechanism (23) provided in the mobile robot hand (2).

  The mobile robot hand (2) moved to the front of the centering unit (3) moves the articulated arm (22) until the silicon substrate (S) is located above the suction stage (31) of the centering unit (3). After that, after the elevating mechanism (23) is lowered and the suction is cut off, the silicon substrate (S) is transferred from the hand (24) onto the suction stage (31) of the centering unit (3). When the transfer is completed, the articulated arm (22) bends and contracts / detaches from the suction stage (31). On the other hand, in the centering unit (3), the suction stage (31) rotates with the silicon substrate (S) sucked and placed, and the centering sensor (32) moves the edge (Δ) of the silicon substrate (S). The suction stage (31) is stopped when the displacement (Δ) reaches the maximum, and then half of the displacement (Δ) is moved in the front-rear direction to move the center and silicon of the centering unit (3). Match the center of the substrate (S). After the centering positioning is completed, the mobile robot hand (2) is actuated and the hand (24) is inserted under the silicon substrate (S). The silicon substrate (S) is lifted from the stage (31), the articulated arm (22) is folded and contracted as it is, and in this state, it moves to the front of the next application unit (4).

  When moving to the front of the coating unit (4), the lifting mechanism (23) and the articulated arm (22) are operated to transfer the silicon substrate (S) onto the spin chuck (44) as described above. Prior to this, in the application unit (4), the elevating cylinder (49a) is operated to lower the base (49), and the spin chuck (44) is exposed upward from the opening (46). At the same time, the lid elevating cylinder (10a) is operated, the elevating lid (10) is lifted and placed, and then the swinging / elevating cylinder (41b) is operated to move the resist supply nozzle (41) outside the spin chuck (44). Keep it in the position. In this state, the lifting mechanism (23) and the articulated arm (22) are operated as described above to move the silicon substrate (S) while being centered on the spin chuck (44).

  When the transfer is completed, the swing / lift cylinder (41b) is operated to move the swing arm (41a) to the silicon substrate (S) side, and the resist supply nozzle (41) at the tip of the swing arm (41a) is then moved to the silicon substrate ( It is lowered to a position immediately above the center of S), and in this state, an appropriate amount of resist (L) is dropped onto the center of the silicon substrate (S). Subsequently, after raising the resist supply nozzle (41), the head is moved to the outside of the silicon substrate (S), and then the upper and lower covers (47) (48) and the base (49) are integrally raised. The silicon substrate (S) is stored in the upper cover (47), and finally the lifting lid (10) is lowered to close the opening (46) of the upper cover (47) to make the inside a closed space. In this state, the spin chuck (44) is rotated, and the resist (L) on the surface is spread on the silicon substrate (S) by the centrifugal force to uniformly apply the resist (L). Excess resist (L) is swung off from the periphery of the silicon substrate (S) by centrifugal force, but the resist (L1) at the periphery is slightly raised by surface tension (see the enlarged view in the circle in FIG. 6). ). When the resist coating is completed, the lifting lid (10), the upper / lower covers (47) (48) and the base (49) are moved up or down as in the beginning, and the silicon substrate (S) is exposed to the outside. . This is taken out by the robot hand (2) and then moved to the front of the adjacent heating / cooling unit (5).

  First, the door (52a) of the heating unit section (50) of the heating / cooling unit (5) is operated to open the access opening (53), and the silicon substrate (S) is inserted into the heating unit section (50). To do. At this time, the support rod raising / lowering motor (59m) is operated to raise the horizontal raising / lowering plate (56) to stop the silicon substrate (S) on the three support rods (54) stopped at the top dead center (= the uppermost position). ) Is transferred from the robot hand (2). When the transfer is finished, the open / close door (52a) is hermetically closed, and then the inside is evacuated. During this time, the three support rods (54) are lowered, the silicon substrate (S) on the support rod (54) is set on the heating plate (51), and heated by the heating plate (51) heated to an appropriate temperature. Then, the resist (L) on the silicon substrate (S) is dried.

  After the resist (L) has dried, the heating unit (50) is returned to atmospheric pressure, and then the three support rods (54) are raised again to lift the silicon substrate (S) and then open and close After the door (52a) is opened, the dried silicon substrate (S) is taken out with the robot hand (2). Subsequently, the silicon substrate (S) is transferred to a cooling unit (59) provided at the lower part of the heating unit (50) and heated in the same manner, and the silicon substrate (S) heated to an appropriate temperature (room temperature, for example, 24 to 25 ° C.). ) And take out with the robot hand (2).

  The cooled silicon substrate (S) taken out is once sent to one chamber (60) of the moisture treatment unit (6) for stocking by the robot hand (2), where it is stocked. If there is no need for stock, the robot hand (2) returns to the coating unit (4) for peripheral rinsing, which is the next step. Here, the case where it returns directly to the coating unit will be described as an example. In addition, since the peripheral part (L1) of the resist (L) of the dried silicon substrate (S) is dried and solidified in a slightly raised state as described above, this part becomes an obstacle in the exposure process, so it is applied again. It is sent to the unit (4), and a peripheral rinse for removing the above-mentioned rising portion (L1) is performed. At the same time, the back surface of the silicon substrate (S) is also cleaned if necessary.

  The stock cooled silicon substrate (S) taken out by the robot hand (2) is sent again to the centering unit (3), where the centering as described above is performed, and then sent to the coating unit (4). It is adsorbed and fixed to the spin chuck (44) by the method described above. Subsequently, as shown in FIGS. 5 and 6, the resist pool removing nozzle (42) is moved to the silicon substrate (S) side beyond the upper cover (47), and then lowered to lower the silicon substrate (S). Set so that the mouth of the removal nozzle (42) faces the resist pool (L1) at the periphery. In this state, the spin chuck (44) is rotated, pure water is sprayed toward the resist pool (L1) of the rotating silicon substrate (S), and the resist pool (L1) is dissolved and removed. The dissolved resist is shaken off by centrifugal force, flows into the drain groove (49c), and is discharged through a water distribution pipe (not shown). In this case, since the periphery of the removal nozzle (42) is surrounded by the nozzle cover (42f), the splash at the time of jetting pure water is not applied to the inner resist (L). At the same time, pure water is sprayed from the back surface cleaning nozzle (43) toward the back surface of the rotating silicon substrate (S), and the back surface cleaning is performed in the same manner. Wash water is shaken off by centrifugal force.

  After removing the resist pool (L1) and cleaning the back surface in this way, the robot hand (2) sends it to the heating / cooling unit (5) again, and heating drying and cooling are performed by the same operations as described above. Then, it is transferred to the next moisture treatment unit (6). The flow is disclosed in FIGS. 10 to 12. First, as shown in FIG. 10, the entrance / exit opening (60a) of the chamber (60) is opened, and the dry silicon substrate (S) is sequentially formed by the robot hand (2). It is inserted into the inside and sequentially placed on the receiving stage (65) provided in the receiving shelf (66). In the drawing, in order to avoid complication, the receiving step (65) is partially shown by a broken line and omitted. Similarly, the silicon substrate (S) is also omitted.

  When the filling of the silicon substrate (S) is completed, the opening shutter (61) is first hermetically closed, then the tilting motor (63) is operated as shown in FIG. 11, and as shown in FIG. ) Tilt the whole back slightly. Further, after the hermetic closing of the entrance / exit opening (60a) by the opening shutter (61) is completed, the inside of the chamber (60) is depressurized to be in a vacuum state, and volatile components in the resist (L) are removed. When the volatile components have been sufficiently removed, the inside of the chamber (60) is returned to atmospheric pressure or filled with nitrogen gas (atmospheric pressure) .After that, pure water is sprayed from the pure water nozzle (68) in the form of a mist, Impregnate the resist (L) with pure water.

  When the pure water treatment is completed, the inside of the chamber (60) is evacuated again and the silicon substrate (S) is vacuum-dried.After that, the inside of the chamber (60) is returned to atmospheric pressure, the opening shutter (61) is opened, Using the robot hand (2), the silicon substrates (S) are transferred one by one to the silicon substrate transfer stage (70) of the exposure unit (7). The silicon substrate (S) placed on the silicon substrate transfer stage (70) is sequentially received by the fixed robot hand (72) of the exposure unit (7), and is placed on the receiving shelf (75a) of the adjacent buffer unit (75). It is sequentially stored in the receiving stage (75b) and waits for the exposure process.

  The exposure process is an existing method, and an example of this is outlined. First, one silicon substrate (S) of the buffer unit (75) is taken out by the fixed robot hand (72) and sent to the exposure centering unit (74). . In the exposure centering section (74), the silicon substrate (S) immediately before being fed into the exposure section (73) is accurately aligned with the centering (XY direction) and the θ direction, and the fixed robot hand is kept in that state. At (72), the wafer is transferred to the silicon substrate inserting / removing part (76) of the exposure part (73). The silicon substrate insertion / removal unit (76) slides the positioned silicon substrate (S) as it is together with the silicon substrate insertion / removal unit (76) and moves it to a predetermined position of the exposure unit (73). The resist is masked onto the resist (L) by ultraviolet rays or other light rays having a short wavelength using the exposure mask on which the pattern is drawn.

  In this exposure process, the following reaction occurs in the resist (L) due to the penetration of pure water (water supply) into the resist (L). Resist (L) used in the present invention is, for example, a positive resist for diazonaphthoquinone novolak thick film, and diazonaphthoquinone is converted into indenketene by exposure, and this indenketene is hydrolyzed with the supplied water in resist (L). A reaction occurs, and indenecarboxylic acid soluble in an alkaline developer is produced. The generation of indenketene by exposure is faster as the amount of moisture increases, and the circuit pattern of the exposure mask is more accurately generated in a larger amount. Therefore, by applying moisture to the resist (L) of the silicon substrate (S) before the exposure process, an extremely accurate and large amount of indenecarboxylic acid generation is formed in accordance with the circuit pattern in the exposure process. As will be described later, in the next development processing, the exposed portion is dissolved in the developer, and accurate sharp development (high resolution and high aspect ratio in the thick film resist process) is performed.

  When the exposure is completed, the exposed silicon substrate (S) is slid again together with the silicon substrate insertion / removal unit (76) and pulled out from the exposure unit (73), and again the buffer unit (75 ) Or a direct return to the silicon substrate transfer stage (70). Then, the exposed silicon substrate (S) is transferred to the developing unit (8) by the mobile robot hand (2). Prior to the transfer, the elevating / lowering cover (82) is lowered to the lowest point, and the elevating / lowering cover (83) is raised to the uppermost point so that the spin chuck (80) is exposed. The developer supply nozzle (84a) and the pure water supply nozzle (84b) are stopped at the home position outside the spin chuck (80). In this state, the mobile robot hand (2) is used to transfer the exposed silicon substrate (S) onto the spin chuck (80).

  When the transfer is completed, the elevating and lowering covers (82) and (83) are respectively raised or lowered and surround the silicon substrate (S) with the elevating and lowering covers (82) and (83) as shown in FIG. At this time, the hood (83c) is stopped in a state where it rises upward. Subsequently, the spin chuck (80) rotates to rotate the silicon substrate (S) placed thereon. In this state, the developer supply nozzle (84a) causes the developer to flow toward the center of the silicon substrate (S). The developer that flows out spreads uniformly on the silicon substrate (S) by centrifugal force, and the development of the resist (L) is accurately performed by the reaction as described above.

  FIGS. 15 (a1, b1) show a state in which a chemical reaction is caused by exposure at a portion corresponding to the through portion (d) of the circuit pattern by exposure, and FIG. 15 (a1) shows that the resist (L) contains moisture. On the other hand, FIG. 15 (b1) shows the case of the conventional example which does not contain moisture. Here, upon exposure, the resist (L) [diazonaphthoquinone as a photosensitizer] decomposes upon exposure to produce indenketene, and the rate of formation of this indenketene increases as the amount of moisture increases, and this indenketene reacts with moisture. To produce indenecarboxylic acid soluble in the developer. Further, the amount of indene carboxylic acid generated due to the amount of water in the resist (L) also changes (that is, the amount of indene carboxylic acid increases as the water content increases).

  Hereinafter, the difference in reaction between the present invention and the conventional example will be schematically described. In the case of FIG. 15 (a1) of the present invention having a high water content, the reaction boundary (Lk) of the exposed portion (Ra) reacts sharply to the bottom surface of the resist (L) because the generation rate of indenketene is high. On the other hand, in the case of FIG. 15 (b1) of the conventional example, the generation rate of indenketene is slow, and as a result, the bottom of the resist (L) does not react sharply, and the reaction boundary (Lk) of the exposed portion (Rb) ) Is inclined.

  FIGS. 15 (a3, b3) are schematic diagrams of the case (a2, b2) etched in the next step, and in FIG. 15 (a3) of the present invention, etching is almost done with the exposure width. In the conventional example [FIG. 15 (b3)], the resolution is inferior as compared with the through portion (d) of the exposure mask (M). In the figure, (E1) and (E2) are etching widths, and FIG. 15 (a3) of the present invention is etched more faithfully to the exposure mask (M), whereas FIG. 15 (b3) is a conventional example. Is less accurate.

  When the above development is completed, the developer supply nozzle (84a) escapes from the silicon substrate (S) to the home position, and instead the pure water supply nozzle (84b) swings on the silicon substrate (S). Then, pure water is poured onto the silicon substrate (S) for cleaning. When the cleaning is completed, the pure water supply nozzle (84b) escapes from the silicon substrate (S) and returns to the home position. The spin chuck (80) keeps rotating for a predetermined time as it is, shakes off moisture on the silicon substrate (S), and ends the rotary drying. When the rotary drying is completed, the spin chuck (80) is stopped, and the developed silicon substrate (S) is fed into the unloader cassette (11b) by the mobile robot hand (2).

Plan view of the device of the present invention Front view of cassette used in the present invention Plan view of the coating unit of the present invention Sectional view of FIG. Plan view of the peripheral rinse mechanism of FIG. Sectional view of FIG. Plan view of the centering unit of the present invention Plan sectional view of the heating and cooling unit of the present invention 9 is a longitudinal sectional view Vertical sectional view of the moisture treatment unit of the present invention A cross-sectional view from the vertical 90 ° direction of FIG. 10 is a longitudinal sectional view showing the water treatment state of FIG. Vertical sectional view of the developing unit of the present invention Plan view of the mobile robot hand of the present invention Developed part comparison enlarged schematic diagram of the developed state of the method of the present invention and the conventional method

Explanation of symbols

(S) Silicon substrate
(L) Resist
(1) Cassette unit
(2) Mobile robot hand
(4) Application unit
(6) Moisture treatment unit
(7) Exposure unit
(8) Development unit

Claims (3)

In a thick film resist water process in which a resist is applied to the surface of a silicon substrate, a circuit formation pattern is exposed to the resist, and the circuit formation pattern is baked.
A thick film resist water process, wherein the resist is exposed after moisture is given to the resist before exposure. (a) a cassette unit for supplying or housing a silicon substrate;
(b) A mobile robot hand for taking out and transferring a silicon substrate from the cassette unit or returning a processed silicon substrate to the cassette unit;
(c) an application unit for applying a resist to the surface of the taken-out silicon substrate;
(d) a moisture treatment unit that dries after applying moisture to the resist of the applied silicon substrate;
(e) an exposure unit that exposes the circuit formation pattern to the resist surface of the dried silicon substrate after moisture application, and burns the circuit formation pattern;
(f) a development unit that develops the resist on the silicon substrate on which the circuit formation pattern is baked;
(g) A thick film resist water process apparatus characterized by the above. The moisture treatment unit used in the thick film resist water process apparatus according to claim 2,
(h) a chamber for storing a silicon substrate;
(i) an opening shutter provided in the chamber and enabling the silicon substrate to enter and exit from the receiving shelf;
(j) a receiving shelf erected in the chamber and having a plurality of rows of receiving stages for silicon substrates;
(k) a moisture supply nozzle for supplying moisture to the silicon substrate in the chamber;
(l) In a state where the silicon substrate is housed in the chamber, vacuum piping for evacuating the chamber before and after moisture supply,
(m) It is composed of a tilting mechanism that tilts the receiving shelf when supplying moisture.
(g) A thick film resist water process apparatus characterized by the above.

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