Abstract:
A transfer mold that is used in production of a component by electroplating and has high workability and superior durability as well as a component produced thereby are provided. A method therefor includes the steps of forming a pattern of a desired component by providing a reverse pattern of the pattern of the desired component on a metal substrate and etching the metal substrate using the reverse pattern as a mask and treating the reverse pattern with heat or removing the reverse pattern and forming an insulation layer in a portion where the reverse pattern has been removed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the National Stage of International Application No. PCT/JP2011/006356 having International filing date 15 Nov. 2011, which designated the United States of America, and which International Application was published under PCT Article 21 (s) as WO Publication 2013/072954 A1 the disclosures of which are incorporated herein by reference in their entireties. 
     
    
     BACKGROUND 
       [0002]    The presently disclosed embodiment relates to a transfer mold manufacturing method, a transfer mold manufactured thereby, and a component produced by the transfer mold. More specifically, the presently disclosed embodiment relates to a method for manufacturing a transfer mold for production of a component by electroplating, a transfer mold manufactured thereby, and a component produced thereby, wherein the transfer mold has high workability and superior durability. 
         [0003]    Electroplating allows formation of a thick film conductor with less restriction in terms of dimension. It is therefore widely used in production of display components such as a dial and hands of a watch, machine components such as a small gear, a spring, a pipe and a diaphragm (pressure sensor) and electronic components such as a wiring of a semiconductor device and a coil. 
         [0004]    Japanese Patent Application Laid-Open No. 2004-1535 discloses manufacturing a cavity insert by: first creating a machined master mold on which a fine pattern has been formed in advance; subsequently creating a transfer master mold by hot press from the machined master mold; and then creating the cavity insert by electroplating from the transfer master mold. 
         [0005]    Japanese Patent Application Laid-Open No. 2004-257861 discloses manufacturing a watch dial by the steps of: forming a mask pattern having openings on a surface of a silicon wafer; performing an anisotropic etching; forming a common electrode film; forming an electroplated film which grows on the common electrode film; etching the silicon wafer; and forming a resin watch dial having protruding portions by using the electroplated film as a transfer mask. 
         [0006]      FIGS. 8   a  and  8   b  show structural drawings of a component formed by using a conventional transfer mold. In  FIG. 8   a , for the purpose of forming a component  80 , a photoresist  30  is patterned on a metal substrate  70  to a shape of the component by partially removing the same. The metal substrate  70 , on which the resist pattern has thus been formed, is used as a transfer mold for electroplating (hereinafter referred to as “EP”) a predetermined metal (Ag, Cu, Ni, etc.) to form the component  80 . 
         [0007]    In  FIG. 8   b , the component  80  molded by EP is transferred onto an adhesive bond  85  and then adhered to a component substrate  90 . In this manner, the component having a given shape depending on its intended use is produced by EP and transferred onto the component substrate  90  for use. 
         [0008]    Here, for ease of release and transfer of the component  80 , the angles β formed at sidewalls of the photoresist  30  are each set to be a blunt angle of less than 45°. In the meantime, when providing an electronic component such as a wiring, a coil, etc. on a semiconductor substrate, it is formed by EP in such a manner that it fills up along the sidewalls of the photoresist  30 . As such, in a case where a wiring pattern, a conductive coil or the like is formed as a long component, it contacts the sidewalls in large area, resulting in increased release resistance in the release and transfer of the component. That is, when using a transfer mold made with patterned photoresist, the transfer of the component onto the component substrate  90  requires an application of a release force that is comparable to the increased release resistance. This causes the edge of the photoresist  30 , which is appressed to the metal substrate  70 , to be easily stripped. In fact, the resist is stripped after a few times of use, and as a result, a problem arises that the transfer mold can then no longer be in use. 
         [0009]    Meanwhile, the conventional manufacture of the display components such as a dial and hands of a watch and machine components such as a small gear, a spring, a pipe and a diaphragm (pressure sensor) by EP is described. These conventional components are produced, in the same manner as the above, according to the steps depicted in  FIGS. 8   a  and  8   b . Here again, depending on the type of the component such as a gear, the metal substrate  70  and the component  80  contact with each other in large area, thereby increasing release resistance in the release and transfer of the component  80  and making the transfer operation difficult. In a case of producing a spring or the like, mutual sidewalls contact in a long area, which causes the release resistance in the release from the sidewalls of the photoresist  30  to increase. As a result, the edge of the pattern of the photoresist  30  can easily be stripped. 
       SUMMARY 
       [0010]    The presently disclosed embodiment has been made in order to solve the above problem, and its purpose is to provide a method for manufacturing a transfer mold having high workability and superior durability for production of a component by EP, a transfer mold manufactured thereby, and a component produced thereby. 
         [0011]    A transfer mold manufacturing method of the presently disclosed embodiment is a method for manufacturing a transfer mold for use in production of a component by electroplating, and it includes steps of: forming, by etching a metal substrate, a pattern of a component having a desired angle at a sidewall thereof by providing a reverse pattern of the pattern of the desired component on the metal substrate and etching the metal substrate using the reverse pattern as a mask; and removing the reverse pattern and forming an insulation layer in a portion where the reverse pattern has been removed. 
         [0012]    The transfer mold manufacturing method of the presently disclosed embodiment is a method for manufacturing a transfer mold for use in production of a component by electroplating, and it includes steps of: forming, by etching a metal substrate, a pattern of a component having a desired angle at a sidewall thereof by providing a reverse pattern of the pattern of the desired component on the metal substrate and etching the metal substrate using the reverse pattern as a mask; and removing the reverse pattern and forming an insulation layer in a portion where the reverse pattern has been removed and on the sidewall of the formed pattern of the component. 
         [0013]    The transfer mold manufacturing method of the disclosed embodiment of the instant application includes, after the step of forming the insulation layer, a step of providing a releasing layer for ease of a release of the component produced by electroplating by depositing or treating with heat. 
         [0014]    A transfer mold according to the presently disclosed embodiment is manufactured by the above transfer mold manufacturing method. 
         [0015]    A transfer mold manufacturing method of the presently disclosed embodiment is a transfer mold manufacturing method in production of a component by electroplating, and it includes steps of: providing a pattern of the component having a desired angle at a sidewall thereof directly on a metal substrate by controlling cutting means; and covering a portion other than the formed pattern of the component or the portion other than the formed pattern of the component and the sidewall of the pattern of the component with an insulation layer. 
         [0016]    The transfer mold manufacturing method of the presently disclosed embodiment includes, in the above transfer mold manufacturing method, following the step of covering with the insulation layer, a step of providing a releasing layer for ease of a release of the component produced by electroplating by depositing or treating with heat. 
         [0017]    The transfer mold manufacturing method of the presently disclosed embodiment includes, in the above transfer mold manufacturing method, following the step of providing the pattern of the component directly on the metal substrate, steps of: providing a releasing layer for ease of a release of the component produced by electroplating by treating with heat; and forming an insulation layer in the portion other than the formed pattern of the component. 
         [0018]    A transfer mold according to the aspects of the disclosed embodiment is manufactured by the above transfer mold manufacturing method. 
         [0019]    A component according to the aspects of the disclosed embodiment is produced by use of the above transfer mold. 
         [0020]    The presently disclosed embodiment makes it possible to provide a transfer mold having high workability and superior durability for production of a component by EP and a component produced thereby. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIGS. 1   a - 1   c  are process drawings showing the steps for manufacturing a transfer mold according to a first aspect of the presently disclosed embodiment. 
           [0022]      FIGS. 2   a - 2   c  are process drawings showing the steps for manufacturing a transfer mold according to an aspect of the presently disclosed embodiment. 
           [0023]      FIGS. 3   a - 3   d  are process drawings showing the steps for manufacturing a transfer mold according to an aspect of the presently disclosed embodiment. 
           [0024]      FIGS. 4   a - 4   d  are process drawings showing the steps for manufacturing a transfer mold according to an aspect of the presently disclosed embodiment. 
           [0025]      FIGS. 5   a - 5   c  are process drawings showing the steps for manufacturing a transfer mold according to an aspect of the presently disclosed embodiment. 
           [0026]      FIGS. 6   a - 6   c  are process drawings showing the steps for manufacturing a transfer mold according to an aspect of the presently disclosed embodiment. 
           [0027]      FIGS. 7   a - 7   c  are drawings showing the steps for manufacturing a component according to the presently disclosed embodiment. 
           [0028]      FIGS. 8   a  and  8   b  are structural drawings showing a component formed by a conventional transfer mold. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    Steps for manufacturing a transfer mold according to the presently disclosed embodiment are described with reference to the drawings.  FIGS. 1   a - 1   c  depict the steps for manufacturing a transfer mold in accordance with the first embodiment. In  FIG. 1   a , a photoresist  30  applied on a metal substrate  10  is subjected to an exposure effected from the direction of the arrows with an intervening photomask  40  having a reverse pattern of a desired component.  FIG. 1   b  shows a resist pattern  30  formed by developing the exposed reverse pattern of the component. In  FIG. 1   c , with use of the resist pattern  30  as a mask, a pattern of the desired component is formed so as to have optional angles a at sidewalls thereof by controlling treatment conditions chemically by chemical etching, etc. or physically by beam etching, etc. 
         [0030]    This is followed by an insulation layer formation process, namely, the resist pattern  30  is either treated with heat so that it is cured and serves as an insulation layer or, alternatively, removed so that an insulation layer  50  of SiO 2  or the like is formed in the portion where the resist pattern  30  has been removed. In this way, the portion other than the pattern is electrically insulated and the transfer mold is completed. Since this transfer mold has the pattern of the desired component engraved thereon and formed integrally with the metal substrate  10 , there is no possibility of the pattern being stripped. As a result, the transfer mold has superior durability. 
         [0031]      FIGS. 2   a - 2   c  are process drawings showing the steps for manufacturing a transfer mold in accordance with the second aspect of the presently disclosed embodiment. Explanation of  FIGS. 2   a  and  2   b  is omitted as they are the same as  FIGS. 1   a  and  1   b . In  FIG. 2   c , the resist pattern  30  has been removed after the treatment thereof. The transfer mold is completed by performing the insulation layer formation process for forming the insulation layer  50  of SiO 2  or the like in the portion where the resist pattern has been removed and on the sidewalls of the desired pattern that has been formed. 
         [0032]      FIGS. 3   a - 3   d  are process drawings showing the steps for manufacturing a transfer mold in accordance with the third aspect of the presently disclosed embodiment. Explanation of  FIG. 3   a  is omitted as it is the same as  FIG. 1   c . In  FIG. 3   b , a releasing layer formation process is performed. That is, for ease of the release of the component to be electroplated, a releasing layer  60  of a metal oxide (AlOx, TiOx, etc.), a nitride or an organic substance (resist) is formed on the entire surface of the side treated in  FIG. 3   a  to such a thickness of 1 to 1000 Å that allows the conductivity thereof to be maintained. The transfer mold is thus completed. The coverage of the entire contact surface between this transfer mold and the component to be produced with the releasing layer  60  makes it possible to further improve releasability. 
         [0033]    Explanation of  FIG. 3   c  is omitted as it is the same as  FIG. 2   c . In  FIG. 3   d , the releasing layer formation process is performed. That is, for ease of the release of the component to be electroplated, the releasing layer  60  of an optional metal oxide (AlOx, TiOx, etc.), a nitride or an organic substance (resist) is formed chemically by CVD (Chemical Vapor Deposition) or physically by sputtering on the entire surface of the side to be treated in  FIG. 3   c  to such a thickness of 1 to 1000 Å that allows the conductivity thereof to be maintained. The transfer mold is thus completed. Similarly to  FIG. 3   b , the coverage of the entire contact surface between this transfer mold and the component to be produced with the releasing layer makes it possible to further improve releasability. 
         [0034]      FIGS. 4   a - 4   d  are process drawings showing the steps for manufacturing a transfer mold in accordance with the fourth aspect of the presently disclosed embodiment. Explanation of  FIG. 4   a  is omitted as it is the same as  FIG. 1   c . Following the insulation layer formation process in  FIG. 4   a , the releasing layer formation process is performed in  FIG. 4   b . That is, the metal substrate  10  is subjected to heat treatment so as to form a metal oxide layer which serves as the releasing layer  60  on the surface thereof to be treated. The transfer mold is thus completed. The coverage of the entire contact surface between this transfer mold and the component to be produced with the releasing layer  60  makes it possible to improve workability. 
         [0035]    Explanation of  FIG. 4   c  is omitted as it is the same as  FIG. 2   c . In  FIG. 4   d , following the insulation layer formation process in  FIG. 4   c , the releasing layer formation process is performed. That is, the metal substrate  10  is subjected to heat treatment so as to form a metal dioxide layer which serves as the releasing layer  60  on the surface thereof to be treated. The transfer mold is thus completed. As the metal surface of this transfer mold is covered by the releasing layer  60 , it is possible to improve workability. 
         [0036]      FIGS. 5   a - 5   c  are process drawings showing the steps for manufacturing a transfer mold in accordance with the fifth aspect of the presently disclosed embodiment. In  FIG. 5   a , conditions for treatment by an electrical beam or cutting means by way of a mechanical cutting tool are controlled in such a manner that a desired pattern of the component having optional angles a at the sidewalls is directly provided on the metal substrate  10  from the direction of the arrows. Then, in  FIG. 5   b , the insulation layer formation process as in  FIG. 1   c  is performed in order to form the insulation layer  50  of SiO 2  or the like in the portion other than the formed pattern. The transfer mold is thus completed. The transfer mold may also be completed by subsequently performing the releasing layer formation process as in  FIG. 3   b.    
         [0037]    Further, in  FIG. 5   c , an insulation layer formation process is performed as in  FIG. 2   c . That is, the resist pattern is removed after the treatment thereof, and the insulation layer  50  of SiO 2  or the like is formed in the portion where the resist pattern has been removed and on the sidewalls of the desired pattern that has been formed. The transfer mold is thus completed. The transfer mold may also be completed by subsequently performing the releasing layer formation process as in  FIG. 3   d.    
         [0038]      FIGS. 6   a - 6   c  are process drawings showing the steps for manufacturing a transfer mold in accordance with the sixth aspect of the presently disclosed embodiment. In  FIG. 6   a , conditions for treatment by an electrical beam or cutting means by way of a mechanical cutting tool are controlled in such a manner that a desired pattern of the component having optional angles a at the sidewalls is directly provided by engraving on the metal substrate  10  from the direction of the arrows. Then, in  FIG. 6   b , the releasing layer formation process is performed. That is, the metal substrate  10  is subjected to heat treatment as in  FIGS. 4   b  and  4   d  so that a metal oxide film which serves as the releasing layer  60  is formed thereon. In  FIG. 6   c , the insulation layer formation process is performed in order to form the insulation layer  50  of SiO 2  or the like as in  FIG. 5   b . The transfer mold is thus completed. 
         [0039]    Now, description is made for the manufacturing method of the component using the transfer mold according to the presently disclosed embodiment.  FIGS. 7   a - 7   c  are drawings showing the steps for manufacturing a component according to the presently disclosed embodiment. In  FIG. 7   a , a desired metal (Ag, Cu, Ni, etc.) is electroplated on, for example, the transfer mold as shown in  FIG. 6   c  to form the component  95 . In  FIG. 7   b , the component  95  molded by EP is, as in  FIG. 8   b , transferred onto the adhesive bond  85  and then adhered to the component substrate  90 . Alternatively, the component  95  is adhered to a green sheet  98  which is then treated with heat for curing. Where the component  95  is adhered to the green sheet  98 , the use of the adhesive bond  85  is eliminated by such softness of the green sheet  98  before curing that the component  95  is buried therein. In this way, the component  95  having a shape with optional angles a at the sidewalls is provided by EP. It can be repetitively molded and transferred onto the substrate  97  or green sheet  98  for diverse intended use. 
         [0040]    The metal substrate  10  may be a plate of a metal such as SUS (Steel Use Stainless), Ni or Cu. A material for electroplating the component  95  may be Ag, Cu, Ni, Au, Sn, Pb, Fe, Cr, Pt, Pd or an alloy of these metals. The releasing layer  60  may be any of a metal oxide (FeOx, NiOx, AlOx, TiOx, CrOx, CuOx, NbOx, VOx, WO), a nitride or an organic resist, and it may have such a thickness (of 1 to 1000 Å, for example) that allows a tunnel current to flow therein. 
         [0041]    As described above, the presently disclosed embodiment is able to provide a transfer mold having high workability and superior durability and a component produced thereby. 
       DESCRIPTION OF REFERENCE NUMERALS 
       [0000]    
       
         
           
               10  metal substrate 
               30  photoresist 
               40  photomask 
               50  insulation layer 
               60  releasing layer 
               80  component 
               85  adhesive bond 
               90  component substrate 
               95  component 
               98  green sheet 
             α inclination angle formed at sidewall 
             β inclination angle formed at sidewall