Method and device for applying solder paste flux

Abstract

A method of applying viscous media on a substrate is disclosed. In the method, the substrate is provided, which is arranged for mounting of electronic components thereon. Further, flux is provided on a deposit of solder paste, which deposit is arranged at a predetermined position on the substrate. The flux is provided by a non-contact dispensing process, such as jetting. By providing flux on the deposit prior to reflow, the risk of quality related issues, such as e.g. graping, advantageously is reduced.

1 . A jetting device for applying viscous media on a substrate for mounting of electronic components thereon, the device comprising:
 at least one non-contact dispensing head assembly, said non-contact dispensing head assembly configured to selectively provide additional flux on at least one deposit among deposits of solder paste that comprise flux, the at least one deposit being arranged at a certain position on the substrate;   wherein the additional flux does not contain any metal particles and is provided by the non-contact dispensing head assembly on top of the deposit in order to partly or fully cover the deposit prior to reflow;   wherein at least a part of the additional flux is provided on at least a part of an electronic component attached to the deposit.   
     
     
         2 . The jetting device according to  claim 1 , further comprising an inspection means configured to inspect the deposit and/or the additional flux. 
     
     
         3 . The jetting device according to  claim 2 , further comprising forming the deposit of additional flux by adding a predetermined amount of flux to a predetermined position according to a printing job or program created in response to inspecting the deposit of solder paste prior to providing the flux. 
     
     
         4 . The jetting device of  claim 1 , said device is further comprising:
 inspection logic configured to identify from an image a sub-range of the solder paste deposits having low deposit volumes below a certain threshold amount and, accordingly, small amounts of flux;   wherein the additional flux is provided on the identified sub-range of the solder paste deposits having low deposit volumes.   
     
     
         5 . A jetting device for applying viscous media on a substrate for mounting of electronic components thereon, the device comprising:
 at least one non-contact dispensing head assembly, said non-contact dispensing head assembly configured to selectively providing additional flux on at least one deposit   among deposits of solder paste that comprise flux, the at least one deposit being arranged at a certain position on the substrate;   wherein the additional flux does not contain any metal particles and is provided by a non-contact dispensing process on top of the deposit in order to partly or fully cover the deposit prior to reflow; and   wherein an amount of the additional flux provided on the deposit is based on a volume of said deposit.   
     
     
         6 . The jetting device according to  claim 5 , further comprising an inspection means configured to inspect the deposit and/or the additional flux. 
     
     
         7 . The jetting device according to  claim 6 , further comprising forming the deposit of additional flux by adding a predetermined amount of flux to a predetermined position according to a printing job or program created in response to inspecting the deposit of solder paste prior to providing the flux. 
     
     
         8 . A screen printer device including an integrated jetting device for applying viscous medium on a substrate, comprising:
 a screen printer configured to screen print deposits of solder paste on predetermined positions on the substrate; and   at least one integrated non-contact dispensing head assembly configured to selectively provide additional flux on at least one deposit among screen printed deposits of solder paste that comprise flux, the at least one deposit being arranged at a certain position on the substrate;   wherein the additional flux does not contain any metal particles and is provided by the integrated non-contact dispensing head assembly on top of the deposit in order to partly or fully cover the deposit prior to reflow;   wherein at least a part of the additional flux is provided on at least a part of an electronic component attached to the deposit.   
     
     
         9 . The screen printer device of  claim 8 , further comprising an inspection means configured to inspect the deposits of solder paste prior to applying the additional flux on the deposits. 
     
     
         10 . The screen printer device of  claim 9 , wherein the flux is provided based on inspecting the deposit and in response to an estimated volume of the deposit being below a threshold value. 
     
     
         11 . The screen printer device of  claim 8 , said device is further comprising:
 inspection logic configured to identify from an image a sub-range of the solder paste deposits having low deposit volumes below a certain threshold amount and, accordingly, small amounts of flux;   wherein the additional flux is provided on the identified sub-range of the solder paste deposits having low deposit volumes.   
     
     
         12 . The screen printer device of  claim 8 , said device is further configured to identify a sub-range of the solder paste deposits having low deposit volumes below a certain threshold amount and, accordingly, small amounts of flux; and
 wherein the additional flux is provided on the identified sub-range of the solder paste deposits having low deposit volumes.   
     
     
         13 . A screen printer device including an integrated jetting device for applying viscous medium on a substrate, comprising:
 a screen printer configured to screen print deposits of solder paste on predetermined positions on the substrate; and   at least one integrated non-contact dispensing head assembly configured to selectively provide additional flux on at least one deposit among screen printed deposits of solder paste that comprise flux, the at least one deposit being arranged at a certain position on the substrate;   wherein the additional flux does not contain any metal particles and is provided by the integrated non-contact dispensing head assembly on top of the deposit in order to partly or fully cover the deposit prior to reflow;   wherein an amount of the additional flux provided on the deposit is based on a volume of said deposit.   
     
     
         14 . The screen printer device of  claim 13 , further comprising an inspection means configured to inspect the deposits of solder paste prior to applying the additional flux on the deposits. 
     
     
         15 . The screen printer device of  claim 14 , wherein the flux is provided based on inspecting the deposit and in response to an estimated volume of the deposit being below a threshold value. 
     
     
         16 . The screen printer device of  claim 13 , said device is further comprising:
 inspection logic configured to identify from an image a sub-range of the solder paste deposits having low deposit volumes below a certain threshold amount and, accordingly, small amounts of flux;   wherein the additional flux is provided on the identified sub-range of the solder paste deposits having low deposit volumes.   
     
     
         17 . The screen printer device of  claim 13 , said device is further configured to identify a sub-range of the solder paste deposits having low deposit volumes below a certain threshold amount and, accordingly, small amounts of flux; and
 wherein the additional flux is provided on the identified sub-range of the solder paste deposits having low deposit volumes.