Mould for electroplating and its manufacturing process

Abstract

A process for manufacturing a mould including: a) providing a first substrate made of photosensitive glass of thickness of at least equal to the height of the mould, b) illuminating the first substrate with UV rays through a mask the windows of which correspond to the depression of the mould in order to create illuminated zones, c) carrying out a heat treatment on the first substrate obtained in step b) in order to crystallize the illuminated zones, d) providing a second substrate having at least one conductive layer on its surface, e) joining the first substrate obtained in step c) with the second substrate so that the conductive layer is located between the first substrate and the second substrate, f) removing the illuminated and crystallized zones of the first substrate so as to uncover the conductive layer, forming a cavity with sidewalls and a bottom occupied by the conductive layer of the mould.

1 . A process for manufacturing a mould comprising the following steps:
 a) providing a first substrate made of photosensitive glass of thickness of at least equal to the height of the mould   b) illuminating said first substrate with UV rays through a mask having windows which correspond to the depression of the mould in order to create illuminated zones   c) carrying out a heat treatment on the first substrate obtained in step b) in order to crystallize the illuminated zones   d) providing a second substrate having at least one conductive layer on its surface   e) joining the first substrate obtained in step c) to the second substrate so that the conductive layer is located between the first substrate and the second substrate   f) removing the illuminated and crystallized zones of the first substrate so as to uncover the conductive layer, in order to form at least one cavity the sidewalls of which and the bottom occupied by the conductive layer of which form said mould.   
     
     
         2 . The process according to  claim 1 , wherein the second substrate is based on silicon. 
     
     
         3 . The process according to  claim 1 , wherein the conductive layer is formed by depositing, on the second substrate, a layer of a metal chosen from the group consisting of chromium, titanium and gold. 
     
     
         4 . The process according to  claim 1 , wherein the step e) of joining the first substrate and second substrate is carried out by soldering the conductive layer of the second substrate to the first substrate. 
     
     
         5 . The process according to  claim 1 , wherein the step e) of joining the first substrate and second substrate is carried out by soldering the first substrate to the second substrate by means of a resist layer provided between the first substrate and the conductive layer. 
     
     
         6 . The process according to  claim 5 , wherein step f) comprises a substep f′) of removing the resist layer uncovered in the cavity after removal of the illuminated and crystallized zones of the first substrate, so as to uncover the conductive layer. 
     
     
         7 . The process according to  claim 1 , wherein the step f) of removing the illuminated and crystallized zones of the first substrate is carried out by chemical etching. 
     
     
         8 . The process according to  claim 1 , wherein a plurality of moulds are produced in the same first substrate. 
     
     
         9 . A process for manufacturing by electroplating a metal micromechanical part, wherein it comprises the following steps:
 g) manufacturing a mould of said micromechanical part using the process for manufacturing a mould according to  claim 1     h) filling the mould with a metal by galvanic growth from the conductive layer in order to form said micromechanical part   i) releasing the micromechanical part obtained in step h) from its mould.   
     
     
         10 . A multi-mould plate intended to manufacture at least one micromechanical part by electroplating, wherein it includes a first substrate made of photosensitive glass of thickness at least equal to the height of the micromechanical part, a second substrate securely fastened to the first substrate, at least one conductive layer provided between the first substrate and second substrate, the first substrate including at least one mould for the micromechanical part, which mould is formed by a cavity formed in said first substrate and the bottom of which is occupied by the conductive layer, allowing a metal to be deposited by galvanic growth in said cavity in order to form said micromechanical part. 
     
     
         11 . The multi-mould plate according to  claim 10 , wherein the second substrate is based on silicon. 
     
     
         12 . The multi-mould plate according to  claim 10 , wherein the conductive layer is a layer of a metal chosen from the group consisting of chromium, titanium and gold. 
     
     
         13 . The multi-mould plate according to  claim 10 , wherein it comprises a resist layer provided between the first substrate and the conductive layer.