Patent ID: 7199882

Claim:
A method for developing information about objects supported on a semiconductor wafer, at least some objects having a curved, specular surface and arranged in an array, the objects being interconnects supported on the wafer, the wafer being either patterned or featureless, the method comprising the steps of: measuring the wafer at a plurality of locations to obtain reference data representative of height variations of the wafer, the step of measuring being carried out using at least one of a triangulation-based scanning sub-system and a confocal scanning sub-system, wherein the triangulation-based scanning sub-system includes a plurality of position sensitive detectors disposed on opposite sides of a plane of an incident scanning laser beam and non-collinear with the scanning laser beam, at least a portion of the incident scanning laser beam being non-normal to an object, the position sensitive detectors configured to receive specular reflected energy and scattered energy from the array of objects; positioning the scanning laser beam relative to the wafer based, at least in part, on the reference data so that a waist of the laser beam coincides with an expected 3D location of the object so as to enhance contrast and obtain at least triangulation-based sensor data; obtaining, with the triangulation-based scanning sub-system, a first set of data representing maximum specular reflections from the curved specular surfaces of the at least some objects in the array; computing height estimate data for the objects in the array utilizing the first set of data; analyzing the height estimate data to obtain an estimate of the height; and obtaining additional information about the objects in the array using a confocal sensor system, wherein the confocal sensor system has a spatial filter and a confocal detector to produce at least one confocal slice of image data and to obtain at least one of confocal defect information and dimensional information of the objects, including an estimate of the diameter of one of the objects having the curved, specular surface.