Patent ID: 6949449
Filing Date: 2005-09-27
Classification: B23K,B28D,H01L,Y10S

Abstract:
1. A method of forming in a ceramic substrate a scribe line that facilitates breakage of the ceramic substrate into separate pieces having side margins defined by the scribe line, the ceramic substrate having a thickness and a surface on or an interior in which is formed a pattern of multiple, mutually spaced apart passive electronic circuit components, the passive electronic circuit components separated by streets along which the scribe line is formed such that the separate pieces created by breakage of the ceramic substrate comprise separate passive electronic circuit components, the method comprising: aligning an ultraviolet laser beam characterized by an energy and a spot size with one of the streets on the surface of the ceramic substrate; imparting relative motion between the ultraviolet laser beam and the ceramic substrate such that the laser beam is directed lengthwise along the street and effects depthwise removal of ceramic substrate material to form a shallow trench, the energy and spot size of the ultraviolet laser beam effecting the depthwise removal in the absence of appreciable melting of the ceramic substrate material so that the trench formed in the ceramic substrate material has a width that converges from the surface to a trench bottom in the form of a sharp snap line; and the shape of the trench forming a region of high stress concentration extending into the thickness of the ceramic substrate and along the snap line to effect, in response to a breakage force applied to either side of the trench, clean breakage of the ceramic substrate into separate passive electronic circuit components having side margins defined by the snap line.