Abstract: With manufacturing tolerances of microelectronic and electro-optical devices being improved to well below a micron, it is becoming increasingly difficult to check both the form of surface features and the presence of defects in a routine manner. These defects may be material or process related. In this paper we demonstrate the advantages of combining advanced optical methods with digital image processing, to form what we call 'Nanoscopy' techniques, for sub- micron surface measurement metrology. We distinguish between two imaging techniques, one for high resolution analysis of near flat surfaces and small features and the other for shape measurement of multi-micron high components. These are combined in the same instrument. The first, Phase Stepping Microscopy (PSM), is illustrated with examples of surface roughness measurement, epilayer defect analysis and feature identification after chemical etching. The second, Peak Fringe Stepping Microscopy (PFSM), is presented with examples of shape measurement of an optical laser guide and a Hetero-structure Bipolar Transistor (HBT).!5
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