JP3469147B2 - Thin film forming equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus, and more particularly to a thin film forming apparatus for transferring a thin film onto a substrate by pressing a substrate and a sheet film on which the thin film is formed. It is. 2. Description of the Related Art A thin film forming method relating to an electronic component mainly comprises:
Sputtering, chemical vapor deposition, vapor deposition, coating,
It can be broadly divided into plating methods and the like. When the area of a substrate on which a thin film is to be formed is small, any one of these methods can be used to handle an electronic component to be realized. However, in recent years, semiconductor substrates have
For example, the diameter has been steadily increased from 200 mm to 300 mm. With the increase in the diameter of wafers used in the manufacture of LSIs and the increase in the area of liquid crystal panels, etc., a thin film forming method suitable for a large area is required. Have been. Also, in the field of multilayer wiring technology in LSI manufacturing technology, it is necessary to flatten the surface of an insulating film with high precision in order to realize multilayer wiring. The demand for technology is also increasing. Heretofore, as typical techniques of this flattening method, (1) SOG (Spin-On-Glass) method and PIQ method (K. Sat method)
o, S.Harada, A.Saiki, T.Kitamura, T.Okubo, and K.Muka
i, "A Nove1 Planar MultilevelInterconnection Techno
logy Utilizing Polyimide ", lEEE Trans.Part HybridPa
ckage., "PHP-9,176 (1973)" (2) Etchback method (P. Elikins, K. Reinhardt, and R.
Layer, "A planarization Process for double metal CM
OS using Spin-on Glass asa Sacrificial Layer, "Proc
eeding of 3rd lnternational IEEE VMIC Conf., 100 (19
86)) (3) Lift-off method (K. Ehara, T. Morimoto, S. Muramoto,
and S.Matsuo, "Planar lnterconnection Technology fo
r LSI Fabrication Utilizing Lift-off Process ", J. Ele
ctrochem.Soc "Vol.131, No.2,419 (1984)) (4) Bias sputtering method (CYTing, VJVivalda and
HGSchaefer, "Study of Planarized Sputter-Deposi
ted-SiO2 ", J. Vac. Sci. Technol. 15, 1105 (1978). (5) Bias ECR method (K. Machida and H. Oikawa," Si
O2 PlanarizationTechnology with Biasing and Electr
on Cyclotron Resonance PlasmaDeposition for Submic
ron Interconnections, "J.Vac.Sci.Technol.B4,818 (198
6)) (6) Polishing method (WJPatrick, WLGuthrie, CLStandle)
y, PMSchiable, "Application of Chemical Mechanical
Polishing to the Fabrication of VLSI Circuit Inter
connections ", J.E1ectrochem.Soc., Vol.138, No.6, Jun
e, 1778 (1991)). Etc. were considered. However, among the above prior arts, S
In the OG method, it is difficult to realize flattening. The etch-back method has a problem of dust generation and dust management is difficult.
The lift-off method does not completely dissolve the stencil material used at the time of lift-off. The bias sputtering method and the bias ECR method have a low throughput and a large damage to the device. The polishing method has a problem that if the film quality of the insulating film is poor, good polishing characteristics cannot be obtained, and none of them has been put to practical use. Further, in the case where the above-mentioned conventional technology is applied to a semiconductor substrate having a large area, it is difficult to secure the flatness of the surface and the uniformity of the film thickness from the viewpoint of controllability. As a result, a complicated process must be added in order to cope with an increase in the area, and there is a problem that the cost is increased. In order to solve such a problem, a thin film forming apparatus for forming a thin film on a substrate by a pressure transfer method has been proposed (for example, Japanese Patent Laid-Open No. 10-18 / 1998).
9566). As shown in FIGS. 7 and 8, the thin film forming apparatus has a sample stage 2 on which a substrate 3 on which a thin film is to be formed is mounted and a heater 4 is provided as a heating means for heating the substrate 3 at a predetermined temperature. The transfer plate 5, which is disposed opposite to the lower part of the sample table 2, is provided with a sheet film 6, and has a heater 8 therein for heating the sheet film 6 at a predetermined temperature, is evacuated by a vacuum pump 9. The transfer plate 5 is disposed in the thin film forming chamber 1, the transfer plate 5 is raised to a predetermined position by a load motor 12 as a load mechanism (FIG. 8B), and the sample table 2 is lowered by the load motor 11 (FIG. 8B). (FIG. 8 (c)) By pressing the substrate 3 against the sheet film 6 for a predetermined time (FIG. 8 (d)), the thin film formed on the surface of the sheet film 6 is transferred to the surface of the substrate 3. That. Further, the transfer plate 5 and the support plate 13 are connected by a plurality of compression coil springs 14 so that the load pressure becomes uniform when the sample table 2 is pressed against the transfer plate 5. Further, the heaters 4 and 8 of the sample table 2 and the transfer plate 5 are controlled by the heater control unit 15, and the outer peripheral edge of the sheet film 6 is held by the film holding mechanism 16. The film holding mechanism 16 is shown in FIG.
As shown in FIG. 1, the sheet film 6 includes a pair of holding members 17a, 17b for holding the front and back surfaces of the outer peripheral edge of the sheet film 6, and actuators 18A, 18B such as air cylinders for moving these holding members 17a, 17b up and down. The film 6 is supplied by an appropriate supply mechanism, and the film
9, the actuators 18A and 18B are operated to hold the sheet film 6 by the holding members 17a and 17b.
Is configured to be held. Nipping body 17a, 17
b are formed in a ring shape, respectively.
A and 18B are provided at equal intervals in the circumferential direction of the sheet film 6, and hold the holding members 17a and 17b, respectively. Reference numeral 20 denotes a frame fixed in the thin film forming chamber 1. However, in the above-described conventional thin film forming apparatus, the film holding mechanism 1
16 only holds the sheet film 6 in a tensioned state, the sheet film 6 is heated by the heater 8.
As shown in FIG. 8 (c), when the thin film is transferred, the thin film is transferred, and when the thin film is transferred, wrinkles are generated on the thin film surface, and the surface is flat and uniform in thickness. However, there is a problem that a thin film cannot be formed.
In addition, all of the conventional apparatuses adopt a method of continuously supplying a sheet film wound in a roll shape, and thus a single-wafer method of supplying a sheet film of a size corresponding to a substrate one by one. There is a demand for the development of a device that employs the above. In that case, the sheet film is formed in a circular shape, and it is essential to develop a mechanism for holding such a circular sheet film in a tensioned state so as not to be loosened. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems and demands, and it is an object of the present invention to surely remove slack of a sheet film caused by thermal expansion in adopting a single-wafer method. Can be
An object of the present invention is to provide a thin film forming apparatus capable of transferring a thin film formed on a sheet film to a large-area substrate with a flat surface and a uniform film thickness. In order to achieve the above-mentioned object, a thin film forming apparatus according to the present invention is provided so as to be relatively movably opposed to each other, and has a facing surface of one of the plates. A substrate is mounted on the first plate, a first and second plates on which a circular sheet film having a thin film is mounted on the opposite surface of the other plate, heating means for heating at least one of the substrate and the sheet film, A weight mechanism for moving at least one of the first plate and the second plate to press the substrate and the sheet film for a predetermined time to transfer the thin film to the substrate; and a weight mechanism disposed around the sheet film. A plurality of film holding and tensioning mechanisms for holding and tensioning the outer peripheral edge of the sheet film, wherein the film holding and tensioning mechanism includes a diameter of the sheet film. A first holding plate which is slidable in the direction, means for moving the first holding plate radially outward of the sheet film when holding the sheet film, and a rotatably mounted on the first holding plate. A second clamping plate, a biasing means for biasing the second clamping plate in the closing direction, and usually the first and second clamping plates by locking the second clamping plate in an open position. An actuator for holding the holding plate at the film holding position and releasing the locked state of the second holding plate when holding the film is provided. In the present invention, when the sheet film is heated by the heating means, the sheet film is stretched to cause a wavy slack. However, since the sheet film is held by the film holding and tensioning mechanism and given a constant tension in the radial direction, the sheet film is stretched and slackened. Is removed. The actuator of the film holding tension mechanism is the second
Is held in the normally open position, and the locked state is released when the film is held. When the second holding plate is released from the actuator, the second holding plate rotates in the closing direction by the urging means, and holds the outer peripheral edge of the sheet film together with the first holding plate. An elastic member such as a spring is used as the urging means. Means for moving the first holding plate radially outward of the sheet film when holding the sheet film include springs,
An actuator such as an air cylinder is used. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a configuration of a thin film forming apparatus according to an embodiment of the present invention, FIG. 2 is a plan view showing a state in which a sheet film of a film holding and tensioning mechanism is sandwiched, and FIGS. ) Is III-III in FIG.
4 is an enlarged cross-sectional view showing a state before and after holding the film, which is broken by a line, FIG. 4 is a cross-sectional view of a wafer, FIG. 5 is a cross-sectional view of a sheet film, and FIGS. FIG. 3 is a diagram illustrating a step of transferring to a substrate. In the figure, the same reference numerals are given to the same components as those shown in the section of the prior art. 1 to 3, the thin film forming apparatus includes a chamber 21 for forming a thin film forming chamber 1 in which the inside can be evacuated, in which first and second plates 2 and 5 are vertically moved. Are housed opposite to each other. The thin film forming chamber 1 can be evacuated from an exhaust port 22 by a vacuum pump 9. The first plate 2 has a wafer (substrate) on the lower surface facing the second plate 5 on which a thin film is to be formed.
The sample stage 3 is formed by mounting the sample stage 3. For this reason, the lower surface of the first plate 2 is provided with a quartz plate 2A polished to ensure flatness, and the wafer 3 is mounted on the quartz plate 2A. Quartz wafer 3
It does not contain substances that contaminate it, and has good processability,
Since the required flatness can be easily obtained, it is excellent as a material for mounting the wafer 3. Further, the first plate 2 includes a heater 4 as a heating means inside. The heater 4 is controlled by the heater control unit 15 and is controlled to be heated between 25 ° C. and 300 ° C. The first plate 2 is suspended from the chamber 21 and is configured to be moved up and down by the load motor 11. The second plate 5 is disposed below the first plate 2 so as to have the same axis, and a transfer plate is formed by mounting a sheet film 6 on the upper surface. The second plate 5 includes a quartz stage 5a on which the sheet film 6 is placed, and a heating table 5b for heating the sheet film 6. The heating table 5b has a heater 8 as a heating means inside. The heater 8 is connected to the heater control unit 15.
And heating is controlled between 25 ° C. and 300 ° C. The second plate 5 is elastically supported on the support plate 13 by a plurality of compression coil springs 14 so that the pressing force is uniform when the substrate 3 and the sheet film 6 are pressed. I am trying to become. The support plate 13 is held by a column 23 so as to be vertically movable, and is configured to be moved up and down by a load motor 12. Such first and second plates 2 and 5 have exactly the same configuration as the conventional sample stage 2 and transfer plate 5 shown in FIG. In FIG. 4, the wafer 3 has a structure in which a semiconductor substrate 26 formed in a disk shape and an Al wiring as an electrode wiring 27 are formed on the semiconductor substrate 26. In the present embodiment, the electrode wiring 27 is formed by forming Al to a thickness of 5000 angstroms by a sputtering method, and then performing patterning by a photolithography process.
Processing was performed by dry etching. In FIG. 5, an insulating film 30 to be a thin film is formed on the surface of the sheet film 6. In the present embodiment, a thermoplastic resin film is used as the sheet film 6. As a thin film, a coating liquid of an SOG material for forming an insulating film was used, and this was applied onto the sheet film 6 to form an insulating film 30 having a thickness of 1 μm or more. Referring again to FIGS. 1 to 3, the thin film forming apparatus further includes a plurality of film holding and tensioning mechanisms 31 for holding and tensioning the sheet film 6 when the insulating film 30 is transferred.
It has. In the present embodiment, an example is shown in which eight film holding and tensioning mechanisms 31 are arranged at equal intervals in the circumferential direction of the sheet film 6 as shown in FIG. The film holding and tensioning mechanism 31 includes an annular guide plate 3 installed horizontally in the chamber 21.
A first holding plate 36 slidably disposed on the sheet film 6 in the radial direction of the sheet film 6, and a second holding member having an intermediate portion rotatably connected to the first holding plate 36 by a shaft 37. A plate 38 is provided. The first holding plate 36 is urged in the radial direction of the sheet film 6, in other words, radially outward by a tension coil spring 39 as urging means, and a slide guide 40 is integrally provided on the lower surface thereof. . The slide guide 40 is slidably inserted into a long hole 41 extending in the moving direction of the first holding plate 36 formed on the guide plate 35, and is prevented from falling out of the long hole 41 by a flange 40a provided at the lower end. ing. On the upper surface of the first holding plate 36, a stopper 42 for locking the second holding plate 38 at an open position shown in FIG. The second holding plate 38 has a U-shape when viewed from the side, and a portion below a bent portion thereof is supported by the shaft 37 and the torsion coil spring 4 mounted on the shaft 37.
4 and is normally locked in an open state by an actuator 45. When the locked state is released when the sheet film 6 is clamped, the sheet film 6 is closed by the force of the torsion coil spring 44 and is closed. 1 clamping plate 36
In addition, the outer peripheral edge of the sheet film 6 is sandwiched. The upper end of the second holding plate 38 is located above the first holding plate 36, and the lower end of the second holding plate 38 passes through the elongated hole 41 and projects below the guide plate 35. Also,
The first and second holding plates 36 and 38 are normally held at the film holding position shown in FIG. In addition, the first,
Concave and convex portions 47 and 48 for preventing the film from slipping are formed on the holding portions for holding the outer peripheral edge of the sheet film 6 on the surfaces of the second holding plates 36 and 38 facing each other. As the actuator 45, an air cylinder, a stepping motor, or the like is used.
5 is fixed to a frame 46 to which it is attached.
It goes without saying that the eight film holding / holding mechanisms 31 arranged around the sheet film 6 operate in synchronization. Further, in the present embodiment, the guide plate 35 is installed horizontally, but the first holding plate 36
The first and second clamping plates 36 and 38 are formed radially outward and obliquely downward at a predetermined angle such that the outer peripheral side is lower than the inner peripheral side. May be moved. Next, a procedure for forming a thin film using the above-described thin film forming apparatus will be described. In the present embodiment, the wafer 3 shown in FIG. 4 is mounted on the lower surface of the first plate 2 with the electrode wiring 27 facing downward. Further, the sheet film 6 shown in FIG. 5 is supplied above the stage 5 a of the second plate 5 with the insulating film 30 facing upward, and the outer peripheral edge portion is held and tensioned by the film holding tension mechanism 31. . That is, when the second holding plate 38 is opened as shown in FIG.
When the liquid is supplied between the second plates 2 and 5 and its outer peripheral edge is placed on the first holding plate 36, the actuator 4
5 is turned off, and the mover 45a is retracted. As a result, the second holding plate 38 is rotated in the closing direction (clockwise in FIG. 3) about the shaft 37 by the force of the torsion coil spring 44, and together with the first holding plate 36, the outer peripheral edge of the sheet film 6. Hold the part. When the movable member 45a is retracted to release the locked state of the second holding plate 38, the first
The holding plate 36 is moved radially outward of the sheet film 6 together with the second holding plate 38 by the force of the tension coil spring 39 to apply a constant tension to the sheet film 6. Therefore, the sheet film 6 is held in a tensioned state. In this state, the insulating film 30 is
The operation of the thin film forming apparatus at the time of transfer to the substrate is as follows. (1) First, the inside of the thin film forming chamber 1 is evacuated by the vacuum pump 10 to a desired degree of vacuum. (2) After a desired degree of vacuum is reached, the heater 4 is energized by a control signal from the heater control unit 15 to heat the first plate 2 to about 200 ° C. and heat the wafer 3 to a desired temperature. I do. Similarly, the heater 8 is energized to heat the second plate 5 to about 200 ° C., and a signal is sent from the control unit to the load motor 12 to start the load operation. As a result, the second plate 5 becomes the sheet film 6
And the stage 5 a is brought into contact with the sheet film 6. Therefore, the sheet film 6 is heated and stretched, but when it is stretched, the first holding plate 3 is correspondingly stretched.
6 moves radially outward by the force of the tension coil spring 39 and continues to apply a constant tension to the sheet film 6, so that wavy slack does not occur. (3) Next, the first plate 2 is lowered by driving the weight motor 11, and the wafer 3 is pressed against the surface of the sheet film 6 (FIG. 6A). (4) The wafer 3 and the sheet film 6 are pressed under a predetermined load for a certain period of time. During that time, the wafer 3 and the sheet film 6 are heated to a predetermined temperature. In the implementation of the present invention, the degree of vacuum in the thin film forming chamber 1 is 10 To
rr or less, the thin film transfer weight 5Kg, heating temperature 2
The heating was performed at 00 ° C. for 10 minutes. (5) When a series of weighting operations is completed, a signal is sent from the control unit to the weighting motors 11 and 12 so that the weighting state becomes zero, and the first and second plates 2 and 5 return to the original initial positions. Let it. At this time, control is performed so that the evacuation is also stopped. (6) Thereafter, the actuator 45 is driven to move the mover 45a forward, and the second holding plate 38 is moved to the position shown in FIG.
, The first and second holding plates 3
The holding state of the sheet film 6 by 6 and 38 is released. At this time, the mover 45a moves forward by a certain amount even after the second holding plate 38 is opened to the maximum angle, and the second holding plate 38
, The first holding plate 36 advances against the tension coil spring 39 and returns to the original initial position. (7) Next, the wafer 3 integrated with the sheet film 6 with the insulating film 30 interposed therebetween is taken out of the thin film forming chamber 1 and the sheet film 6 is peeled off as shown in FIG. The wafer 3 on which the insulating film 30 is formed as shown in FIG. (8) After the sheet film 6 is peeled off, a heat treatment step is further performed to fire the insulating film 30. In this embodiment, the heat treatment was performed at a temperature of 400 ° C. for a time of 30 minutes. As described above, the thin film forming apparatus according to the present invention is provided with the film holding and tensioning mechanism 31 so that the sheet film 6 is held in a tensioned state. Even when thermally expanded, no wavy slack occurs at all, and a thin film having a flat surface and a uniform thickness can be transferred to the wafer 3 even if the wafer 3 has a large area. If the sheet film 6 is held in a tensioned state by the film holding / tensioning mechanism 31, the sheet film 6 does not move when the wafer 3 and the sheet film 6 are pressed. Further, since a constant tension is applied to the sheet film 6 by the film holding and tensioning mechanism 31, the amount of elastic deformation in the thickness direction can be reduced. In the above embodiment, an example is shown in which the wafer 3 is mounted on the first plate 2 to be used as a sample stage, and the sheet film 6 is mounted on the second plate 5 to be used as a transfer plate. However, the present invention is not limited to this, and the first plate 2
May be used as a transfer plate, and the second plate 5 may be used as a sample stage. In the above-described embodiment, the first plate 2 and the second plate 5 are connected to the weighted motors 11 and 12.
However, it is also possible to adopt a configuration in which only one of them is moved up and down. In the above embodiment, the motors 11 and 12 are used as the weighting mechanism to apply the weight. However, the present invention is not limited to this, and the first and second plates 2 and 2 may be used.
Other means may be used as long as it is a mechanism that pressurizes 5 and 5.
In the above-described embodiment, the sheet film 6 made of the thermoplastic synthetic resin film is used. However, the present invention is not limited to this, and it goes without saying that a metal film or the like may be used. In the above-described embodiment, the tension coil spring 39 is used as means for moving the first holding plate 36 radially outward of the sheet film 6 when holding the sheet film 6. Although the first holding plate 36 is retracted in synchronization with the rotation of the second holding plate 38 in the closing direction, the present invention is not limited to this. After the holding plate 38 is completely closed and the sheet film 5 is held together with the first holding plate 36, the first holding plate 36 can be retracted. In addition, although the insulating film is formed on the sheet film 6, the insulating film is not limited to the insulating film as long as it can be formed on the sheet film, and another thin film, for example, a metal-based thin film may be formed. . Furthermore, in the above-described embodiment, an example in which a thin film is formed on a semiconductor substrate has been described. However, the present invention is not limited to this. It goes without saying that it can be applied. As described above, according to the thin film forming apparatus according to the present invention, when the sheet film is held in a tensioned state by the film holding / tensioning mechanism and is expanded by thermal expansion, the first holding plate is formed. Since it is configured to move radially outward and always apply a constant tension, no wavy slack occurs, and therefore, even on a large-area substrate, a thin film with high flatness can be easily formed on the surface. And at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic sectional view showing a configuration of a thin film forming apparatus according to an embodiment of the present invention. FIG. 2 is a plan view showing a state in which a sheet film of a film holding and tensioning mechanism is sandwiched. 3 (a) and 3 (b) are enlarged cross-sectional views showing the state before and after the film is clamped, taken along the line III-III in FIG. FIG. 4 is a sectional view of a wafer. FIG. 5 is a sectional view of a sheet film. FIGS. 6A to 6C are diagrams illustrating a process of transferring an insulating film to a semiconductor substrate. FIG. 7 is a schematic sectional view showing a configuration of a conventional thin film forming apparatus. FIGS. 8A to 8D are diagrams showing the operation of the apparatus. [Description of Signs] 1 ... thin film forming chamber, 2 ... first plate, 3 ... wafer, 4
... heater, 5 ... second plate, 6 ... sheet film, 8 ... heater, 11, 12 ... weighted motor, 31 ...
Film holding tension mechanism, 36: first holding plate, 38: second holding plate, 39: tension coil spring, 44: torsion coil spring, 45: actuator.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Izeki Izumi Ueyama, located in Dainippon Screen Manufacturing Co., Ltd. 1 at Tenjin Kitacho 4-chome, Horikawa-dori-Teranouchi, Kamigyo-ku, Kyoto-shi, Kyoto (72) Located at 1-chome Tenjin-Kitamachi, Horikawa-dori-Teranouchi, Kamigyo-ku, Kyoto-shi, Kyoto, Japan Dainippon Screen Manufacturing Co., Ltd. (56) References JP-A-6-37004 (JP, A) 247643 (JP, A) JP 2001-7367 (JP, A) JP 11-145060 (JP, A) JP 10-189566 (JP, A) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) H01L 21/31 H01L 21/312 H01L 21/316

Claims (1)

(57) [Claim 1] A substrate is provided so as to be relatively movably opposed to each other, a substrate is mounted on a facing surface of one of the plates, and a thin film is provided on a facing surface of the other plate. First and second plates on which a circular sheet film is mounted; heating means for heating at least one of the substrate and the sheet film; and moving at least one of the first plate and the second plate A weighting mechanism for pressing the substrate and the sheet film for a predetermined time to transfer the thin film to the substrate; and a plurality of film holders disposed around the sheet film for holding and tensioning the outer peripheral edge of the sheet film. A tension mechanism, wherein the film holding tension mechanism comprises a first holding plate slidable in the radial direction of the sheet film, and the first holding plate being a sheet. Means for moving the sheet film radially outward when holding the film, a second holding plate rotatably mounted on the first holding plate, and urging the second holding plate in the closing direction. And the first and second holding plates are held in the film holding position by locking the second holding plate in an open position, and the second holding plate is held when the film is held. A thin film forming apparatus comprising: an actuator for releasing a locked state.