Twodimensional nanometerscale calibration based on onedimensional gratings
Abstract
: This paper describes the construction of a lateral nanometerscale line standard and an easy method for the lateral calibration in the submicron range. The calibration is based directly on the atomic arrangement in a superlattice and is done by using the cross section of alternating layers grown by molecular beam epitaxy (MBE) as a transfer standard. Equidistant line spacings of 10 and 30 nm were routinely imaged for calibration. A linear transformation of the scanned and uncorrected images into an image with the line spacing of the transfer standard can be defined. We define this transformation by three parameters: an x and a y correction factor, C_{x} and C_{y}, and the angle between the scanned x axis and the scanned y axis. From only three images of lines the calibration parameters can be calculated analytically. From more than three images the correction parameters can be estimated using a leastsquares fitting technique. Using this method we have calibrated a tube scanner. For a scan area of 1000 nm×1000 nm, we have measured C_{x} and C_{y} with relative standard uncertainties (k=1) of 0.5% and 0.9%, respectively and γ with a standard uncertainty of 0.7^{°}. This work is done to obtain traceability in the important submicrometer range as no commercial calibration objects are available with lateral dimensions between 200 nm and 1 nm.
 Publication:

Applied Physics A: Materials Science & Processing
 Pub Date:
 1998
 Bibcode:
 1998ApPhA..66S.831G
 Keywords:

 PACS: 06.20;
 07.79