Method of manufacturing laminated ceramic electronic parts

Abstract

A method useful for the manufacture of multilayer ceramic electronic components such as a multilayer chip inductor, a multilayer transformer, a multilayer hybrid components containing a coil conductor, and the like comprises a process A for preparing a ceramic green sheet, a process B for forming a through hole to the ceramic green sheet, a process C for forming a conductor pattern on the ceramic green sheet, and a process D for stacking said ceramic green sheet to another ceramic green sheet, wherein said process B is executed by irradiating a laser beam onto the ceramic green sheets so as to form through holes to the fragile ceramic green sheet with a pinpoint accuracy.

1 . A method of manufacturing multilayer ceramic electronic components, including: 
 a process A for preparing a ceramic green sheet;    a process B for forming a through hole to said ceramic green sheet;    a process C for forming a conductor pattern on the ceramic green sheet; and    a process D for stacking said ceramic green sheet to another ceramic green sheet, wherein said process B is executed by irradiating a laser beam onto the ceramic green sheets.    
     
     
         2 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 said process A is executed by forming a ceramic green sheet on a base film; and    said process D is executed by a step of stacking the ceramic green sheet the another ceramic green sheet and a step of peeling the base film from the stacked green sheet.    
     
     
         3 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 said process C is executed by the step of forming the conductor pattern on the base film and a step of forming the green sheet on the base film on which the conductor pattern is formed; and    said process D is executed by a step of stacking the ceramic green sheet to the another ceramic green sheet and a step of peeling the base film from the stacked green sheet.    
     
     
         4 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 said process A is executed by forming the ceramic green sheet on a base film; and    said process D is executed by a step of cutting the ceramic green sheet on the base film to a predetermined size, a step of peeling the cut ceramic green sheet from the base film and a step of stacking the peeled ceramic green sheet to the another ceramic green sheet.    
     
     
         5 . A method of manufacturing multilayer ceramic electronic components according to    claim 4   , wherein each of said sheet cutting step, said sheet peeling step and said sheet stacking process is executed using a cutting head provided with a suction means.  
     
     
         6 . A method of manufacturing multilayer ceramic electronic components according to    claim 4   , wherein said process C includes a step of forming positioning marks to the ceramic green sheet for subsequent processes.  
     
     
         7 . A method of manufacturing multilayer ceramic electronic components according to    claim 4   , wherein said process B includes a step of forming positioning marks to the ceramic green sheet for subsequent processes.  
     
     
         8 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process C is executed by a step of preparing a transfer film composed of a base film on which a conductor layer is formed and a step of thermally transferring the conductor layer of the transfer film onto the ceramic green sheet in a predetermined pattern shape.  
     
     
         9 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process C is executed by a step of preparing a transfer film composed of a base film on which a conductor pattern is formed and a step of thermally transferring the conductor pattern of the transfer film onto the ceramic green sheet.  
     
     
         10 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 said process A is executed by forming the ceramic green sheet on a base film; and    said process D is executed by thermally transferring the ceramic green sheet on the base film onto the another ceramic green sheet in a predetermined size.    
     
     
         11 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 said process A is executed by preparing a film made by forming the ceramic green sheet on a base film; and    said process D is executed by a step of punching the ceramic green sheet on the base film to a predetermined size together with the base film, a step of stacking the punched ceramic green sheet to the another ceramic green sheet and a step of peeling the base film from the stacked ceramic green sheet.    
     
     
         12 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process B is executed by irradiating a laser beam onto the light transmitting portion of a mask and irradiating the laser beam having passed through the light transmitting portion onto the ceramic green sheet.  
     
     
         13 . A method of manufacturing multilayer ceramic electronic components according to    claim 12   , wherein the laser beam is intermittently irradiated onto the green sheet while continuously moving the ceramic green sheet in a predetermined direction.  
     
     
         14 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process B is executed by irradiating a laser beam onto the light transmitting portion of a mask, reflecting the laser beam having passed through the light transmitting portion by a galvano-mirror and irradiating the reflected laser beam onto the ceramic green sheet.  
     
     
         15 . A method of manufacturing multilayer ceramic electronic components according to    claim 14   , wherein the laser beam is caused to intermittently incident on the galvano-mirror while continuously changing the reflecting angle of the galvano-mirror in a predetermined direction.  
     
     
         16 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process B is executed by irradiating a laser beam to the light transmitting portion of a mask, focussing the laser beam having passed the light transmitting portion by a lens and irradiating the laser beam to the ceramic green sheet at an image-forming ratio by which an irradiated shape is made smaller than the shape of the light transmitting portion.  
     
     
         17 . A method of manufacturing multilayer ceramic electronic components according to    claim 16   , wherein the laser beam is irradiated to a plurality of the light transmitting portions disposed to the mask and a plurality of the laser beams having passed through the respective light transmitting portions is irradiated to the ceramic green sheet to thereby collectively form through holes as many as the laser beams.  
     
     
         18 . A method of manufacturing multilayer ceramic electronic components according to    claim 16   , wherein the laser beam irradiated portion of the ceramic green sheet is covered with a suction cover which permits the laser beam to pass therethrough and air is supplied into the suction cover from the outside when the laser beam is irradiated and then the air is sucked and exhausted to the outside.  
     
     
         19 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein: 
 a laser beam having a normal pulse determined by an output and a pulse duration is used as a laser beam to be irradiated;    the values of the peak power and the pulse duration is set so that the product of them is equal to a quantity of heat capable of melting and vaporizing a sheet material corresponding to the volume of a through hole; and    the value of the pulse duration is restricted to a time range in which a film temperature does not reach the melting temperature thereof.    
     
     
         20 . A method of manufacturing multilayer ceramic electronic components according to    claim 19   , wherein the energy value of the outer periphery of the irradiated energy is smaller than that of the center thereof.  
     
     
         21 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein said process C is executed by a step of forming a groove on the surface of the ceramic green sheet and a step of forming the conductor pattern in the groove.  
     
     
         22 . A method of manufacturing multilayer ceramic electronic components according to    claim 21   , wherein an irregular portion is formed in the groove at said groove forming step.  
     
     
         23 . A method of manufacturing multilayer ceramic electronic components according to    claim 21   , wherein the width of the groove formed at said groove forming step is made larger than the width of the conductor pattern.  
     
     
         24 . A method of manufacturing multilayer ceramic electronic components according to    claim 21   , wherein a chamfered portion is formed along the opening end of the groove at the groove forming step.  
     
     
         25 . A method of manufacturing multilayer ceramic electronic components according to    claim 1   , wherein a plurality of through holes are formed in a predetermined region which overlaps the end of the conductor pattern.  
     
     
         26 . A method of manufacturing multilayer ceramic electronic components according to    claim 25   , wherein the size and position of the region where the through holes are formed are set based on the range of a positional dislocation which may be caused when the through holes are formed.  
     
     
         27 . A method of manufacturing multilayer ceramic electronic components according to    claim 25   , wherein the through holes are formed to a polygonal shape.