Method for imaging electrical barrier layers such as pn-junctions in semiconductors by means of processing particle-beam-induced signals in a scanning corpuscular microscope

US4646253A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Hans Rehme · Zorneding, DE
• Helmut Schink · Munich, DE

Key dates

• Filing date: Apr 12, 1984
• Grant date: Feb 24, 1987
• Expiry date: Apr 12, 2004

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R31/2653
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for high-precision imaging of electrical barrier layers (pn-junctions) in semiconductors by means of processing particle beam induced signals created during scanning with a corpuscular microscope, even when the electrical barrier layers are aligned perpendicularly or obliquely relative to a specimen surface. The path of the pn-junctions in cross-sections through semiconductor components may be identified with a high reliability such as within 0.1 .mu.m. Specific point (P(x,y), P(x+.DELTA.x, y+.DELTA.y), M(x,y), N(x,y), F(x,y)) is defined and particle beam induced signals generated along a scan line containing this specific point is compared with reference to particle beam induced signals generated along a further scanning line containing a point within a certain environment of the specific point first chosen with the comparison results being used to localize the electric barrier region profile.