Housing for an electronic device

Claim 1

A method for the manufacture of a housing for an electronic device, characterized by the following steps: (a) forming a ceramic substrate, (b) piercing holes in the substrate to accommodate mounting pins of a housing and providing an area for accommodation of an electronic device, (c) metallizing the holes and forming conducting rings around the holes on each side of the substrate, these operations being carried out by screen-printing using a conducting ink which is made of, at least, copper and a vitreous-crystalline material, said conducting ink being fired in a neutral atmosphere at a temperature lower than the melting temperature of copper, said operations comprising the steps of depositing an amount of said conducting ink at the opening of the holes, diffusing the ink in the holes by reflowing, and firing the layers of said conducting ink thus obtained, (d) depositing a first conducting layer in a pattern to form conductors for interconnecting part of the terminals of the electronic device to part of the pins, leaving free the area for accommodating the electronic device, said deposition being carried out by screen-printing using a conducting ink comprising copper, said ink being identical to or compatible with the ink used for metallising the holes and the rings; and firing said first conducting layer, (e) depositing an insulating layer in a pattern where two successive conducting layers are isolated, thereby leaving free the area for accommodating the electronic device as well as the conducting rings and the ends of the conductors located opposite the terminals of the electronic device, said deposition process being carried out by screen-printing using an insulating vitreous-crystalline ink fired in a neutral atmosphere at a temperature compatible with that of the conducting ink, said insulating ink having a coefficient of expansion very close to that of the substrate up to the firing temperature of said insulating layer, and firing said insulating layer. (f) alternately depositing conducting and insulating layers, respectively, to form a multilayer circuit in a pattern of a network of conductors necessary for interconnecting the terminals of the electronic device and the pins of the housing, thereby leaving free said area for accommodating the electronic device as well as the conducting rings and the ends of the conductors located opposite the terminals of the device, said alternate deposition processes being carried out by screen-printing with types of ink being alternately conductive and insulative, said types of ink being identical to or compatible with the conducting and insulating ink forming the preceding layers, the last layer of said alternate layers being a protective insulating layer, and firing said alternating conducting and insulating layers individually one by one upon depositing each alternating layer, (g) temporarily protecting the zones which are formed by the area for accommodating the electronic device and the ends of the conductors located opposite said area by using a varnish resistant to a solder used for fixing metal mounting pins, (h) locating said metal mounting pins consisting of a shank provided with a flat head, said shank going through said substrate at the location of the holes, said pins sufficiently projecting from one of the faces to ensure a proper fixation of the housing, said flat head being supported by the conducting ring located at the other face of the substrate, and, subsequently, soldering the pins using a metal alloy which is compatible with the metal coating of the holes and rings at a melting temperature being lower than or substantially equal to the firing temperature of the multicircuit layers, (i) removing the protective varnish, (j) locating and fixing the electronic device in the area reserved at the substrate, (k) providing flexible metal wires between the terminals of the electronic device and the ends of the conductors of the multilayer circuit which are left free, and (l) fixing as protective cap over the electronic device.

Claim 2

A method for the manufacture of a housing for an electronic device, characterized by the following steps: (a) forming a ceramic substrate, (b) piercing holes in the substrate to accommodate mounting pins of a housing and providing an area for accommodation of an electronic device, (c) metallizing the holes and forming conducting rings around the holes on each side of the substrate, these operations being carried out by screen-printing using a conducting ink which is made of, at least, copper and a vitreous-crystalline material, said conducting ink being fired in a neutral atmosphere at a temperature lower than the melting temperature of copper, said operations comprising the steps of depositing an amount of said conducting ink at the opening of the holes, diffusing the ink in the holes by reflowing, and firing the layers of said conducting ink thus obtained, (d) depositing a first conducting layer in a pattern to form conductors for interconnecting part of the terminals of the electronic device to part of the pins, leaving free the area for accommodating the electronic device, said deposition being carried out by screen-printing using a conducting ink comprising copper, said ink being identical to or compatible with the ink used for metallising the holes and the rings; and firing said first conducting layer, (e) depositing an insulating layer in a pattern where two successive conducting layers are isolated, thereby leaving free the area for accommodating the electronic device as well as the conducting rings and the ends of the conductors located opposite the terminals of the electronic device, said deposition process being carried out by screen-printing using an insulating vitreous-crystalline ink fired in a neutral atmosphere at a temperature compatible with that of the conducting ink, said insulating ink having a coefficient of expansion very close to that of the substrate up to the firing temperature of said insulating layer, and firing said insulating layer. (f) alternately depositing conducting and insulating layers, respectively, to form a multilayer circuit in a pattern of a network of conductors necessary for interconnecting the terminals of the electronic device and the pins of the housing, thereby leaving free said area for accommodating the electronic device as well as the conducting rings and the ends of the conductors located opposite the terminals of the device, said alternate deposition processes being carried out by screen-printing with types of ink being alternately conductive and insulative, said types of ink being identical to or compatible with the conducting and insulating ink forming the preceding layers, the last layer of said alternate layers being a protective insulating layer, and firing said alternating conducting and insulating layers individually one by one upon depositing each alternating layer, (g) temporarily protecting the zones which are formed by the area for accommodating the electronic device and the ends of the conductors located opposite said area by using a varnish resistant to a solder used for fixing metal mounting pins, (h) locating said metal mounting pins consisting of a shank provided with a flat head, said shank going through said substrate at the location of the holes, said pins sufficiently projecting from one of the faces to ensure a proper fixation of the housing, said flat head being supported by the conducting ring located at the other face of the substrate, and, subsequently, soldering the pins using a metal alloy which is compatible with the metal coating of the holes and rings at a melting temperature being lower than or substantially equal to the firing temperature of the multicircuit layers, (i) removing the protective varnish, (j) locating and fixing the electronic device in the area reserved at the substrate, (k) providing flexible metal wires between the terminals of the electronic device and the ends of the conductors of the multilayer circuit which are left free, and (l) fixing as protective cap over the electronic device.