JP2007074003A - Method of manufacturing semiconductor device and semiconductor manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a conductor layer without performing wet plating. <P>SOLUTION: In a method of manufacturing a semiconductor device, a main component material 24 of a conductive thin film 25 is implanted on the surface of a semiconductor substrate 10 (Fig. 1(c)); after that, the conductive thin film 25 is lapped thereon under a vacuum atmosphere (Fig. 1(d1)); and the substrate is exposed to a high pressure atmosphere with the conductive thin film 25 being lapped (Fig. 1(d2)). Thereby, the conductive thin film 25 is attached firmly to underlying layers 11 and 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a semiconductor device manufacturing method and a semiconductor manufacturing apparatus in which an active element or the like is formed on a surface layer of a semiconductor substrate, and more specifically, a conductor layer such as a metal wiring over the active element or other connection terminals. The present invention relates to a technique for forming on the surface of a semiconductor substrate.

  2. Description of the Related Art Conventionally, when forming a metal wiring layer on the surface of a semiconductor substrate in a manufacturing process of an LSI or the like (semiconductor device), a step of forming a groove below the metal wiring layer and embedding the metal in the groove It has been known. FIG. 5 shows the order in which the copper layer is formed on one main surface of a semiconductor substrate, that is, the surface on which a functional element such as a transistor is formed.

  More specifically, a large number of ICs (semiconductor devices) are usually formed on the upper surface, ie, one main surface, of a thin silicon wafer 10 (semiconductor substrate) having a diameter of about 300 mm and a thickness of 1 mm or less (see FIG. 5A). Looking at a longitudinal section of a part thereof (see FIG. 5B), in the state immediately before the formation of the copper layer for wiring, for example, the silicon oxide film 12 formed on the surface of the substrate 11 is used. The contact hole 13 to the PN junction and other active elements formed in the surface layer of the substrate 11 and the wiring pattern region connected thereto are removed by a photolithography process or the like. The contact hole 13 is removed up to the surface of the substrate 11 or other contact surface, and the wiring region around the contact hole 13 is removed so that the oxide film 12 remains at the bottom of the groove.

  When forming a copper wiring on the silicon wafer 10, a very thin copper layer 14 is first attached to the upper surface by sputtering or CVD (see FIG. 5C), and then copper is formed by wet plating. A copper layer 15 is grown on the layer 14 (see FIG. 5D). Thus, after the copper layer 15 is formed on the main surface of the silicon wafer 10, the main surface is subjected to CMP (chemical mechanical polishing) to remove the copper layer 15 other than the wiring region (FIG. 5). (See (e)).

  The copper layer 15 formed through such a copper deposition process by sputtering or CVD and a subsequent copper growth process by wet plating has an isotropic internal crystal. In addition, the boundary portion between the silicon 11 and the oxide film 12 there is almost no eutectic, and the boundary surface is clear (see FIG. 5F).

When an aluminum layer or an aluminum alloy layer is formed at the copper layer 15, a conductor layer is formed to a desired film thickness by a growth method such as CVD or PVD, and then heated. It is embedded in the contact hole 13 by flowing (refer to Patent Documents 1 and 2 below), or the gap at the contact hole 13 is crushed by applying pressure in addition to heating (see Patent Document 3 below) Techniques for doing this are also known. However, since these materials are premised on the formation of a film thickness that is larger than the conventional one using aluminum having a relatively low melting point, the melting point is higher than that and the growth rate tends to be slow from the viewpoint of processing time. Not practical for copper.
JP-A-2-213471 Japanese Patent Laid-Open No. 2-205678 JP 7-193063 A

  On the other hand, aluminum that has been grown and grown has become difficult to withstand electromigration along with miniaturization. In particular, the higher the growth rate, the more porous the entire conductor layer becomes. Unlike a big gap, it doesn't collapse easily. Therefore, in forming the conductor layer, copper other than the aluminum-based metal is used as the conductive material, and a process for accelerating the deposition growth is also employed.

  As described above, in the conventional semiconductor device and the manufacturing method thereof, when the conductor layer cannot be formed only by the dry process such as sputtering or CVD, not only aluminum but also other conductor materials such as copper are considered. In this case, wet plating is used in the conductor growth process. However, in order to apply wet plating to microfabrication of a semiconductor device, it is necessary to always keep a plating solution or the like strictly and properly. For this reason, the management and work of the process are strict. Furthermore, disposal of the waste liquid is troublesome. Therefore, it becomes a problem to omit the wet process from the process of forming the conductor layer on the semiconductor device.

  In addition, the conductor formed by plating has a weak adhesion and adherence to the lower layer and easily causes interfacial peeling, and is difficult to become dense and tends to decrease in strength. Therefore, it is also a problem to improve the adhesion to the lower layer and to increase the strength of the conductor layer formed on the surface of the semiconductor device.

  The present invention has been made to solve such a problem, and an object thereof is to realize a method for manufacturing a semiconductor device in which a conductor layer is formed without using wet plating. Another object of the present invention is to realize a semiconductor device in which a conductor layer is in close contact with a lower layer. Another object of the present invention is to realize a semiconductor device having a strong conductor layer.

  The configuration and operational effects of the present invention for solving such problems will be described below.

  A method of manufacturing a semiconductor device according to the present invention includes a step of stacking a conductive thin film on a surface of a semiconductor substrate in a vacuum atmosphere, and a step of exposing them to a high pressure atmosphere while being stacked. It is. That is, a step of stacking (matching) a conductive thin film on a (main) surface of a semiconductor substrate (on which an active element or the like is formed on one main surface) in a vacuum atmosphere (arrangement, mounting, etc.) And a step of exposing them to a high-pressure atmosphere while overlapping (combining) them (and thereby applying pressure from above the conductive thin film to attach the conductive thin film onto the one main surface). .

  In such a method for manufacturing a semiconductor device, when forming a conductor layer on the surface of a semiconductor substrate, first, a conductive thin film is overlaid on the surface of the semiconductor substrate in a vacuum atmosphere. Thereby, both can be combined without interposing air or gas. Next, they are exposed to a high pressure atmosphere in the overlapping state. Then, the conductive thin film is pressed and pressed against the surface of the semiconductor substrate, and is bent and deformed so as to conform to the surface shape. In addition, since there is almost no air, gas, or the like between the two, the boundary surfaces thereof closely contact each other, and even after the pressurization is stopped, peeling due to the expanding gas or the like does not occur.

  Accordingly, the conductive layer is deposited on the semiconductor device only in a dry atmosphere such as a vacuum atmosphere and a high-pressure atmosphere, without using a wet process of immersing in a liquid. In addition, the conductive thin film, which is thinned separately from the substrate, is usually manufactured by a rolling process or a process that takes tensile elongation into the rolling, so it is in a dense state and is deposited and grown. More resistant to electromigration than things. Therefore, according to the method for manufacturing a semiconductor device of the present invention, a high-quality conductor layer can be formed without using wet plating.

  Another method for manufacturing a semiconductor device according to the present invention is the above-described method for manufacturing a semiconductor device, wherein the main component material of the conductive thin film is implanted into the (primary) surface of the semiconductor substrate prior to the stacking step. It is a method characterized by including a process.

  In such a method of manufacturing a semiconductor device, a eutectic of a conductive material and an existing material is formed where the main component material of the conductive thin film is implanted. Then, a conductor layer is pressure-bonded thereon, but the conductor and its eutectic are close to each other and are easily adapted to each other. Thereby, the adhesive force between the conductor layer and the underlying material is strengthened by the eutectic. Therefore, according to the method for manufacturing a semiconductor device of the present invention, the adhesion between the conductor layer and the lower layer can be improved.

  The semiconductor device according to the present invention is characterized in that in the semiconductor device provided with the conductor layer, a eutectic is formed so as to be interposed between the conductor layer and a material therebelow.

  In such a semiconductor device, the cohesiveness of both or a component close thereto is interposed between the conductor layer and the underlying material, whereby the adhesion between the two is reinforced. Therefore, according to the present invention, it is possible to realize a semiconductor device in which the conductor layer is in close contact with the lower layer.

According to another semiconductor device of the present invention, in the semiconductor device provided with the conductor layer, the conductor layer has an internal crystal extending along the lower surface of the conductor layer. Features.
In such a semiconductor device, the inner crystal of the conductor layer extends along the lower surface of the conductor layer. However, a thin or elongated crystal substance generally extends and is resistant to deformation. Such a conductor can withstand bending force applied when it is applied to a semiconductor substrate, subsequent thermal deformation stress, and migration force due to high-density current. Therefore, according to the present invention, a semiconductor device having a strong conductor layer can be realized.

As is clear from the above description, in the method for manufacturing a semiconductor device of the present invention, the conductor layer is deposited and formed only in a dry atmosphere such as a vacuum atmosphere and a high-pressure atmosphere. There is an advantageous effect that it is possible to dispense with wet plating when forming the conductor layer on the surface of the semiconductor device.
Further, in the method of manufacturing a semiconductor device and the semiconductor device of the present invention, the adhesion between the conductor layer and the lower layer in the semiconductor device can be improved by strengthening the adhesion by interposing a eutectic. There is an advantageous effect that.
Furthermore, the semiconductor device of the present invention has an advantageous effect that a semiconductor device having a strong conductor layer can be realized by introducing a specific crystal structure into the conductor layer. .

  About the semiconductor device of this invention and its manufacturing method, the concrete form for implementing this is demonstrated referring drawings. Hereinafter, a series of steps of the manufacturing method (see FIG. 1), the structure of the manufactured semiconductor (see FIG. 2), and the structure and operation (see FIGS. 3 and 4) of two types of semiconductor manufacturing apparatuses are sequentially performed. explain.

  The semiconductor device manufacturing method shown in FIG. 1 differs from the conventional method shown in FIG. 5 in that a copper ion implantation process (FIG. 5C) is used instead of the copper layer 14 formation process (see FIG. 5C) by sputtering or the like. 1 (c)) and a series of mounting steps (see FIG. 5) for depositing the copper foil 25 instead of forming the copper layer 15 by wet plating (see FIG. 5 (d)). 1 (d1)) and a pressurizing step (see FIG. 1 (d2)). The copper foil 25 is manufactured in advance by a rolling process separately from the silicon wafer 10. In the rolling process, as in the piano wire drawing process, in addition to rolling, stretching is also performed, so that it can be kept to a minimum without heating or changing the crystal structure even if heated, so the finished copper foil 25 is a dense and strong thin film.

  The copper ion implantation process is commonly performed using an ion implantation apparatus called an implanter. In this case, in order to reduce the work burden of creating the mask, the contact hole 13 and the wiring pattern region around it are used. The mask used in the photolithography process is shared. Then, copper ions are implanted so as to enter the shallow surface portion of the exposed surface of the substrate 11 and the oxide film 12 at the groove bottom corresponding to the wiring region (see FIG. 1C). The thin copper ion implantation layer 24 becomes a Si—Cu eutectic by mixing the implanted copper ions with silicon or the like of an existing material that has received the ions. The reason why the copper ions are implanted is that this is the main component of the copper foil 25. When another conductor is formed instead of copper, the main component material is implanted. Such a process is a step of implanting the main component material of the conductive thin film into the main surface of the semiconductor substrate prior to the next mounting step.

  The mounting process is a process of placing a thin copper foil 25 having a thickness of about 1 μm (preferably 0.1 μm or less) on the upper surface, that is, the main surface of the silicon wafer 10 (see FIG. 1D1). The copper foil 25 is gently placed in a state where it is spread flat so as to cover the entire main surface of the silicon wafer 10. At this time, the copper foil 25 is processed in a vacuum chamber 30 to be described later so that the copper foil 25 overlaps the oxide film 12 except for the groove and stepped portion. Therefore, such treatment is a process of stacking a conductive thin film on the surface of the semiconductor substrate in a vacuum atmosphere.

  Further, the silicon wafer 10 on which the copper foil 25 is placed is continuously subjected to a high pressure gas of about 900 atm using a pressurizing unit 41 which will be described later without being taken out from the vacuum chamber 30. Such a process is a process of exposing the semiconductor substrate and the conductive thin film to a high-pressure atmosphere while overlapping them. Then, the copper foil 25 whose upper surface is pressurized by the high-pressure gas is strongly pressed against the upper surface of the silicon wafer 10. Thus, the copper foil 25 also extends into the contact hole 13 and the surrounding grooves, and the lower surface is in close contact therewith (see FIG. 1 (d2)).

  Then, the copper foil 25 is pressed against the copper ion implantation layer 24 at the adhesion boundary surface and strongly adheres. Further, since the lower surface of the copper foil 25 extended without being exposed to oxygen-containing air is fresh and has low contact resistance, the electrical connection state to the active element and the like is also good. Further, the rolled copper foil 25 is tenaciously extended during its extension and deforms to conform to the surface shape of the lower layer without breaking anywhere. Thereafter, as in the prior art, the main surface is subjected to CMP treatment, and the copper layer 25 other than the wiring region is removed (see FIG. 1E).

[Example of Semiconductor Device]
Thus, when the crystal structure of the semiconductor layer 25 in particular is seen with respect to the semiconductor device in which the conductor layer 25 is formed, FIG. 2A shows a detailed cross-sectional schematic view of the portion. The copper ion implantation layer 24 directly below the deposited copper foil 25 is a Si—Cu eutectic, and the silicon wafer 10 having such a copper ion implantation layer 24 includes a conductor layer, a material thereunder, The eutectic intervening is formed. The lower surface of the copper foil 25 is firmly attached to the copper ion implantation layer 24.

  In addition, when the copper foil 25 is rolled, the lower surface of the conductive thin film crystal pattern 25a which is thinly extended while being spread in a planar shape and formed into a substantially parallel multilayer is pressed against the exposed surface of the substrate 11 or the oxide film 12. Since it is bent slightly to extend to match the step shape, a curved pattern that is the same as or similar to the exposed surface of the substrate 11 or the oxide film 12 is drawn while maintaining a parallel state that inherits the parallel state. Deform. The conductor layer 25 leaving the thin multilayer crystal pattern 25a deformed in this way has an internal crystal extending along its lower surface.

  Note that the conductor layer 25 having the crystal structure shown in the schematic cross-sectional view in FIG. 2B is formed at the contact hole 13 in order to eliminate the recess remaining after the CMP at the contact hole 13. A metal plug 26 is embedded. This step is performed by depositing a metal such as tungsten by MOCVD or the like before the copper ion implantation step. Also in this case, the conductor layer 25 has an internal crystal extending along the lower surface thereof, and a eutectic is formed directly therebelow.

  Moreover, in the above manufacturing process, in order to strengthen the adhesion between the copper foil 25 and its lower layer, a step of implanting copper ions 24 was employed instead of the process of forming the copper layer 14 by sputtering or the like. If it is in time for the conventional level, the copper layer 14 is formed extremely thin by CVD or the like as before, and only the subsequent wet plating process is replaced by the mounting process and the pressing process of the copper foil 25. Also good.

  And these semiconductor devices manufactured by such a manufacturing process are excellent in electrical conductivity, and have a high resistance to electromigration, as well as good production efficiency, compared to conventional devices manufactured by conventional manufacturing methods. It has a number of advantages.

[First Embodiment of Semiconductor Manufacturing Apparatus]
The first apparatus whose vertical cross-sectional structure is shown in a schematic diagram in FIG. 3A is a semiconductor manufacturing apparatus suitable for performing the mounting process and the pressurizing process among the processes described above. In order to perform both processes continuously, the vacuum pump 33 (vacuum atmosphere generating means) and the lift table 34 (semiconductor substrate holding means + distance variable means) are used for the chamber 30 (vacuum atmosphere securing means). A pressure unit 41 (high pressure atmosphere generating means), a copper foil supply unit 51 (conductive thin film supply means), and a laser unit 56 (copper foil cutting means + copper foil annealing means) are added.

  The vacuum chamber 30 is covered with a lid portion made of an aluminum plate in order to secure a vacuum atmosphere in the internal space of the main body portion obtained by hollowing out aluminum. An opening is formed through the side wall so that the wafer transfer arm 61 can be taken in and out of the vacuum chamber 30 when the silicon wafer 10 (semiconductor substrate) is carried in and out. A gate 31 for opening and closing the opening is attached. Although not shown in the figure, the gate 31 and the wafer transfer arm 61 are surrounded by a evacuated spare chamber so that the silicon wafer 10 can be loaded and unloaded without breaking the vacuum state.

Vacuum pump 33, such as a mechanical booster and turbomolecular pump is used in conjunction in a single stage or in multiple ^{stages, 10 -6~-7 Torr (133} × 10 -6~-7 Pa) by performing evacuation to the extent In order to generate a vacuum atmosphere in the internal space of the vacuum chamber 30, the vacuum chamber 30 is connected to the vacuum chamber 30 through a valve 32 so as to be capable of being sucked and exhausted. An auxiliary valve 37 is also added as appropriate for the purpose of relief when the inside of the vacuum chamber 30 is returned to atmospheric pressure or the exhaust by the vacuum pump 33 is not in time.

  The lift 34 is made of a stainless steel plate, and is processed and formed to be slightly larger than the silicon wafer 10 so that the loaded silicon wafer 10 can be mounted and held, and the upper surface thereof is finished flat. One end of the bellows 35 is hermetically welded to the lower surface of the bellows 35, and the other end of the bellows 35 is hermetically welded to the periphery of the through hole in the inner bottom of the vacuum chamber 30. The elevating platform 34 is supported by a column 36 inserted therethrough. The elevator 34 is driven from the outside by a pulse motor, a ball screw, or the like (not shown) through a support column 36 so that the elevator 34 can move up and down. The movable range of the lift 34 is lower than the position where the wafer transfer arm 61 enters, beyond the feeding height of the copper foil 25 (described later) and further above the position. In this case, it reaches a position higher than the lower end of the sleeve 42 described later. As a result, the lift 34 is integrated with means for changing the distance between the semiconductor substrate and the conductive thin film and means for changing the distance between the semiconductor substrate and the high-pressure atmosphere. In addition, a heating element (not shown) is embedded in the lifting platform 34 in order to heat the silicon wafer 10 on the upper surface.

The pressurizing unit 41 is fixedly attached to the lid portion of the vacuum chamber 30 from above, and argon gas or nitrogen gas is passed through the lid portion into the lumen of the sleeve 42 extending into the internal space of the vacuum chamber 30. Etc., and the pressure is increased to about 900 atmospheres (see Patent Document 4 below). The sleeve 42 is manufactured by processing a thick stainless steel so as to withstand high pressure, and is formed in a shape such that the upper end portion of the lift platform 34 that has risen enters the air tightly with respect to the lower end portion of the lumen. Thus, in this apparatus, a high-pressure atmosphere is generated by the pressurizing unit 41 attached to the vacuum chamber 30, and the high-pressure atmosphere is locally secured by the sleeve 42 and the lifting platform 34 fitted thereto. It has become.
JP-A-9-292182

  The copper foil supply unit 51 is obtained by winding a copper foil 25 rolled into a strip shape with an appropriate constant thickness of several μm to 1 μm or less around a rotatable shaft, and is stored in an airtight outer cylinder. Is filled with nitrogen to prevent oxidation. Further, only the top portion of the copper foil 25 is taken out from the outer cylinder in advance in consideration of setting under atmospheric pressure. And when the surroundings are in a vacuum state, the drawer opening of the copper foil 25 is opened, and when the leading portion of the copper foil 25 is pulled, the shaft core rotates and the copper foil 25 is fed one after another. Yes. As a result, in this apparatus, means for continuously supplying the conductive thin film without being exposed to the outside air is provided in the vacuum chamber.

  In the vacuum chamber 30, in addition to the copper foil supply unit 51, a pair of upper and lower copper foil feed rolls 52 provided in the vicinity thereof, and a pair of upper and lower copper foils provided on the opposite side at the same height as these. There are also a foil drawing roll 53 and a tension roll 54 and a copper foil winding unit 55 provided in the vicinity thereof. Then, the copper foil 25 coming out of the copper foil supply unit 51 is first sandwiched between the copper foil feed rolls 52 and sent out along with their rotation, passes between the lifting platform 34 and the sleeve 42, and then again. It is pinched by the copper foil drawing roll 53 and is drawn toward the copper foil winding unit 55 as they rotate. Further, the copper foil 25 is given an appropriate tension by the tension roll 54 so as not to loosen, and is finally wound and stored by the copper foil winding unit 55. As a result, the conductive thin film 25 is held in the vacuum chamber 30 between the lifting platform 34 and the sleeve 42. In order to supply the copper foil 25 in various thicknesses without replacing the copper foil supply unit 51, the copper foil feed roll 52 may be re-rolled using a rolling roller.

  As the laser unit 56, a laser unit 56 whose output power and diaphragm condition can be adjusted so that the laser light can be strengthened to cut or weaken the copper foil 25 to perform heating for annealing. In addition, the lid of the vacuum chamber 30 can be scanned over the entire upper surface of the silicon wafer 10 on the lifting platform 34 and its peripheral region with respect to the copper foil 25 that is just above the lifting platform 34. It is attached at the side of the sleeve 42 to the inner surface of the part.

  The use mode and operation of the semiconductor manufacturing apparatus having such a configuration will be described with reference to the drawings. 3 (b) to 3 (e) are schematic longitudinal sectional views showing the operation state of the main part, and FIG. 3 (f) is a view of the conductive thin film supplied and used from above. It is. In addition, the following operation | movement procedure is performed when each unit and a mechanism part operate | move according to control of a suitable controller.

  When the silicon wafer 10 is carried by the wafer transfer arm 61 onto the lifting platform 34 that is lowered downward, the vacuum chamber 33 is evacuated by the vacuum pump 33 and the lifting platform 34 is raised in the vacuum atmosphere. (See FIG. 3B). A polyimide adhesive 27 is applied in advance to the edge of the upper surface of the silicon wafer 10. Then, when the polyimide adhesive 27 slightly contacts the lower surface of the copper foil 25, the elevator 34 is temporarily stopped, and there, the silicon wafer 10 or the upper surface of the elevator 34 has a circular shape having the same size as the upper surface. The upper copper foil 25 is cut out by the laser unit 56 (see FIG. 3C). Thus, the conductive thin film 25 is overlaid on the surface of the semiconductor substrate 10 in a vacuum atmosphere.

  Then, the elevator 34 is raised again, and the upper surface and the upper end of the elevator 34 are inserted into the inner cavity of the lower end of the sleeve 42 while the cut copper foil 25 and the silicon wafer 10 are placed (see FIG. 3D). ). In this state, the lumen of the sleeve 42 is pressurized to about 900 atm by the pressurizing unit 41, and the silicon wafer 10 is heated to about 250 ° C. by a heating element incorporated in the lifting platform 34. In this way, the silicon wafer 10 and the copper foil 25 are left over and exposed to a high pressure atmosphere.

  Thereafter, after the pressure in the inner cavity of the sleeve 42 is lowered, the lifting platform 34 is lowered with the silicon wafer 10 placed thereon, and returns to the height of the copper foil 25 stretched between the rolls 52 and 53. Then, the laser light is irradiated by the laser unit 56 to the copper foil 25 that is pressure-bonded to the silicon wafer 10. This irradiation is performed while scanning at high speed with low illuminance. Thus, the annealing treatment of the copper foil 25 is instantaneously performed locally so as not to affect the lower layer, and the stress relaxation and further improvement of the adhesion of the copper foil 25 are also achieved.

  Finally, when the elevator 34 is lowered again and returned to the initial height, the silicon wafer 10 thereon is unloaded by the wafer transfer arm 61 and the strip-shaped copper foil 25 stretched between the rolls 52 and 53 is made of copper. A predetermined length is sent from the foil feed roll 52 side to the copper foil drawing roll 53 side, and a new copper foil 25 that has not yet been cut arrives on the lifting platform 34. Thus, the loading process and the pressurizing process for one silicon wafer 10 are continuously performed in the vacuum chamber 30 and preparations for the next silicon wafer 10 are made.

  In this example, in order to prevent the copper foil 25 on the silicon wafer 10 from slipping and to prevent the high-pressure gas from entering between the silicon wafer 10 and the copper foil 25 during pressurization. The polyimide adhesive 27 is applied to the silicon wafer 10, but an inorganic gasket may be used instead. In this case, it is possible to heat to 500 to 600 ° C.

[Second Embodiment of Semiconductor Manufacturing Apparatus]
The second device, whose vertical cross-sectional structure is shown schematically in FIG. 4 (a), also differs in configuration from the first device, but is also suitable for mounting and pressurizing among the above steps. Device. This differs from that of the first embodiment described above in that a copper foil support arm 71 is provided in the vacuum chamber 30 in place of the copper foil supply units 51 to 55 and the laser unit 56. In addition to the wafer transfer arm 61, a copper foil transfer arm 62 is also provided above the vacuum chamber 30.

  The copper foil 25 used in this apparatus is cut into a disk shape in advance and individually inserted into an annular plastic frame 28 (see FIG. 4B). The copper foil support arm 71 has a vacuum chamber at the rear end so that the conductive thin film is held between the lifting platform 34 and the sleeve 42 by supporting the plastic frame 28 of the copper foil 25 at the front end. It is attached to the inner surface of 30 side walls. Three copper foil support arms 71 having the same height are provided so that the holding state is stabilized.

  The use mode and operation of the semiconductor manufacturing apparatus having such a configuration will be described with reference to the drawings. 4 (b) to 4 (f) are schematic longitudinal sectional views showing the operating state of the main part.

  First, the silicon wafer 10 is carried in by the wafer transfer arm 61 on the lifting platform 34 that is lowered downward, and the copper foil 25 is carried in by the copper foil transfer arm 62, and the plastic frame 28 of the copper foil 25 is moved. It is supported by the tip of the copper foil support arm 71. Further, the inside of the vacuum chamber 30 is made high vacuum by the vacuum pump 33, and the lifting platform 34 is raised in the vacuum atmosphere (see FIG. 4B). When the lifting platform 34 is raised to the copper foil support arm 71, the plastic frame 28 is transferred from the copper foil support arm 71 onto the lifting platform 34 (see FIG. 3C). Thus, the conductive thin film 25 is overlaid on the surface of the semiconductor substrate 10 in a vacuum atmosphere.

  Then, the lifting platform 34 continues to rise and stops when the tip of the plastic frame 28 surrounding the copper foil 25 enters the inner cavity of the lower end of the sleeve 42 (see FIG. 4D). In this state, the inner cavity of the sleeve 42 is preliminarily pressurized slightly by the pressing unit 41. This preloading is performed to such an extent that the plastic frame 28 is pushed and spreads and is lightly adhered to the inner surface of the sleeve 42 (see FIG. 4E). In this way, even if the copper foil 25 is spread and wrinkles or the like exist, it is surely flattened. Further, the airtightness is also enhanced around the gap between the copper foil 25 and the silicon wafer 10.

  Thereafter, the elevator 34 is raised again while maintaining the preload, and the upper surface and the upper end of the elevator 34 are inserted into the inner cavity of the lower end portion of the sleeve 42 while the copper foil 25 and the silicon wafer 10 are placed (see FIG. 4 (f)). In this state, the lumen of the sleeve 42 is fully pressurized to about 900 atm by the pressurizing unit 41, and the silicon wafer 10 is heated to an appropriate temperature by a heating element incorporated in the lifting platform 34. . In this way, the silicon wafer 10 and the copper foil 25 are left over and exposed to a high pressure atmosphere.

  Finally, after the pressure in the inner cavity of the sleeve 42 is lowered, the lifting platform 34 is lowered to the initial height while the silicon wafer 10 is placed, and the silicon wafer 10 thereon is carried out by the wafer transfer arm 61. In this way, the loading process and the pressurizing process for one silicon wafer 10 are continuously performed in the vacuum chamber 30, and the preparation for receiving the next silicon wafer 10 and the copper foil 25 is also made.

It is the process example about the manufacturing method of the semiconductor device of this invention. It is a cross-sectional schematic diagram of a characteristic part about a semiconductor device. It is a 1st example of the semiconductor manufacturing apparatus suitable for implementation of this invention. It is a 2nd example of the semiconductor manufacturing apparatus suitable for implementation of this invention. It is an example of the conventional semiconductor manufacturing process.

Explanation of symbols

10 Silicon wafer (semiconductor substrate, semiconductor device)
11 Substrate (foundation)
12 Oxide film (insulating layer, laminated part, lower layer of conductor layer)
13 Contact hole (wiring location on active element, conductor layer formation location)
14 Copper layer (conductor adhesion layer)
15 Copper layer (conductor growth layer)
24 Copper ion implantation layer (implantation layer of main component of conductor, lower eutectic part)
25 Copper foil (conductive thin film, conductor layer)
25a Crystal pattern (crystal distribution, crystal stretch structure)
26 Metal plug (hole filling material, step relief)
27 Polyimide adhesive (inorganic gasket, airtight member, sealing material)
28 Plastic frame (copper foil holding member, airtight member, sealing material)
30 Vacuum chamber (sealing means, vacuum atmosphere securing means)
31 Gate (loading / unloading sealing means, vacuum atmosphere securing means)
32 Valve 33 Vacuum pump (evacuation means, vacuum atmosphere generation means)
34 Elevator (board mounting table, atmosphere transfer means, high pressure atmosphere securing means)
35 Bellows 36 Prop 37 Auxiliary valve 41 Pressurizing unit (high-pressure atmosphere generating means)
42 Sleeve (Measuring means for high-pressure atmosphere)
51 Copper foil supply unit (conductive thin film feeding means)
52 Copper foil delivery roll (conductive thin film rolling means)
53 Copper foil drawing roll 54 Tension roll 55 Copper foil winding unit (conductive thin film storage means)
56 Laser unit (copper foil cutting means, copper foil annealing means)
61 Wafer transfer arm (semiconductor substrate loading / unloading means)
62 Copper foil transfer arm (conducting thin film carrying in / out means)
71 Copper foil support arm (means for holding conductive thin film in vacuum)

Claims (9)

A step of stacking a conductive thin film on the surface of a semiconductor substrate in a vacuum atmosphere;
And a step of exposing to a high-pressure atmosphere with the conductive thin film overlaid on the surface of the semiconductor substrate.   The method of manufacturing a semiconductor device according to claim 1, further comprising a step of implanting a main component material of the conductive thin film on the surface of the semiconductor substrate prior to the superimposing step.   The method for manufacturing a semiconductor device according to claim 1, further comprising a step of applying an adhesive to an edge of the semiconductor substrate prior to the overlapping step. A vacuum chamber;
A table for holding a semiconductor substrate in the vacuum chamber;
A vacuum atmosphere generation means for generating a vacuum atmosphere by exhausting the gas in the vacuum chamber;
Conductive thin film supply means for mounting a conductive thin film on the semiconductor substrate in the vacuum chamber;
High-pressure atmosphere generating means for generating a high-pressure atmosphere attached to the vacuum chamber and exposing the semiconductor substrate on which the conductive thin film is mounted to a high-pressure atmosphere;
A semiconductor manufacturing apparatus comprising:   The conductive thin film supply means includes metal foil supply means for supplying a strip-shaped metal foil wound around an axis, and cutting means for cutting the metal foil into a desired shape by a laser. The semiconductor manufacturing apparatus according to claim 4.   The semiconductor manufacturing apparatus according to claim 4, wherein the conductive thin film supply unit includes a metal foil supply unit that supplies a metal foil fixed to a frame.   5. The semiconductor manufacturing apparatus according to claim 4, wherein the high-pressure atmosphere generating unit includes a sleeve that is fitted to a table that holds the semiconductor substrate and pressurizes a lumen.   The said sleeve is attached to the said vacuum chamber of the upper part of the stand holding the said semiconductor substrate, The stand holding the said semiconductor substrate can be raised to the position which fits with the said sleeve. Semiconductor manufacturing equipment.   The semiconductor manufacturing apparatus according to claim 4, further comprising annealing means for annealing the conductive thin film with a laser.

Images