Microelectronics inspection system

Claim 1

A system for inspection of microelectronic assemblies having internal microcircuit chips with terminals electrically connected by wire bonding means to circuit conductive traces on a mounting substrate, wherein chip bodies and interconnection elements including wires, ball bonds, and bond wedges which may be visually discriminated against similar reflective backgrounds, comprising: a plurality of concentric light ring source means for illumination of said chips and interconnection elements placed under the center of each said concentric light ring; a plurality of focusing means for directing each said light ring source at a predetermined angle of incidence relative to said microcircuit so that optimal contrast is obtained between reflections from said chip bodies and interconnection elements and similar background trace reflections (;), wherein said focusing means comprise: at least one said focusing means for directing a first said light ring at an illumination angle off vertical which is sufficiently large so as to separate the reflection from rounded inspection objects from conductor background traces made of a similar material; at least a second said focusing means directing a second said light ring at an illumination angle off vertical which is sufficiently small so as to separate the reflection from inspection objects having variable sloped surfaces from substrate background traces made of a similar material; and first switching means for simultaneously directing said first and second said light rings so as to separate the reflection from inspection objects having flat body surfaces from other substrate and inspection object background reflections; first optical means for collecting said light reflections from said chip bodies and interconnection elements emanating along a fixed axis through the concentric centers of both said ring lights and for redirecting said reflections for viewing, said first optical means comprising: second optical turning means for directing said collected reflections away from said concentric center; a plurality of magnification camera means, each having a separate input magnification lens means, for substantially simultaneous conversion of optical images into electronic signals; third optical beam splitting means for separating said reflected light from said second optical turning means into a separate optical beams directed to each said input magnification means; and second switching means for activating any selected one or more said camera means to convert said light into said electronic signals; and viewing means for visual inspection of said chip bodies and interconnection elements in order to determine bonding defects.

Claim 2

A system for inspection of microelectronic assemblies having internal microcircuit chips with terminals electrically connected by wire bonding means to circuit conductive traces on a mounting substrate, wherein chip bodies and interconnection elements including wires, ball bonds, and bond wedges which may be visually discriminated against similar reflective backgrounds, comprising: a plurality of concentric light ring source means for illumination of said chips and interconnection elements placed under the center of each said concentric light ring; a plurality of focusing means for directing each said light ring source at a predetermined angle of incidence relative to said microcircuit so that optimal contrast is obtained between reflections from said chip bodies and interconnection elements and similar background trace reflections (;), wherein said focusing means comprise: at least one said focusing means for directing a first said light ring at an illumination angle off vertical which is sufficiently large so as to separate the reflection from rounded inspection objects from conductor background traces made of a similar material; at least a second said focusing means directing a second said light ring at an illumination angle off vertical which is sufficiently small so as to separate the reflection from inspection objects having variable sloped surfaces from substrate background traces made of a similar material; and first switching means for simultaneously directing said first and second said light rings so as to separate the reflection from inspection objects having flat body surfaces from other substrate and inspection object background reflections; first optical means for collecting said light reflections from said chip bodies and interconnection elements emanating along a fixed axis through the concentric centers of both said ring lights and for redirecting said reflections for viewing, said first optical means comprising: second optical turning means for directing said collected reflections away from said concentric center; a plurality of magnification camera means, each having a separate input magnification lens means, for substantially simultaneous conversion of optical images into electronic signals; third optical beam splitting means for separating said reflected light from said second optical turning means into a separate optical beams directed to each said input magnification means; and second switching means for activating any selected one or more said camera means to convert said light into said electronic signals; and viewing means for visual inspection of said chip bodies and interconnection elements in order to determine bonding defects.