Browse Prior Art Database

Panoramic Switchable Array SEM Detector

IP.com Disclosure Number: IPCOM000107195D
Original Publication Date: 1992-Jan-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 3 page(s) / 64K

Publishing Venue

IBM

Related People

Hopewell, WD: AUTHOR [+3]

Abstract

Disclosed is a scanning electron microscope detector design that allows electron detection over an integrated sphere.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 73% of the total text.

Panoramic Switchable Array SEM Detector

       Disclosed is a scanning electron microscope detector
design that allows electron detection over an integrated sphere.

      Image contrast in the scanning microscope is well known to
depend on the location of the electron detector with respect to
imaged sample.  In practice, detector arrangements involving more
than a few independent sensors are unknown in scanning electron
microscopes.  This article introduces a new concept, an electrically
selectable array of detectors placed within a section of a sphere.
The system consists of 15 channel plate detectors placed to form
radially oriented 5 x 3 arrays along a hemisphere of approximately 5
inches (see Figs. 1A and 1B).  The cross section of the array in the
X travel direction of the scanning electron microscope stage has the
detectors equally distributed about an arc of 120o of aperture.  In
the Y direction, the detectors are in 3 rows over a 60o arc.  The
detector is connected to the microscope stage such that it tilts when
the sample is tilted, thus maintaining the collection geometry.

      The detectors are powered by the same source C and all detector
feed parallel bus D to the scanning electron microscope E video Z
axis.  However, the sum of the output of the detectors is
electronically selectable by a summing device (not shown) placed
within the bus D.  In this way the contrast ratio within the sensing
elements can be varied and analyzed as a functio...