This paper presents the characterization of step structures at multiple scales using a metrological AFM rig based on nano measuring machine. The AFM system achieves a measurement range of 25 mm × 25 mm × 5 mm with sub-nanometer resolution. An AFM signal amplifier is designed to match the signals of the AFM scanner and the NMM controller, and to increase noise attenuation. Step-height standards of 500 nm, 10 µm and 2 mm have been measured and evaluated using the presented AFM system. Methods to characterize ultra-high steps and sidewalls are also introduced.
A nano dimensional standard named SIMT100 was designed and fabricated. The standard consists of a tracking area, a step height area, a 1D grating area, and a 2D grating area. All the structures were fabricated with a height of 100 nm in a 3 mm × 3 mm silicon substrate. To calibrate the standard, a white light interference microscope was constructed and integrated to the nano measuring machine (NMM). The height of a 10 μm width step measured by white light interference (WLI) microscope was 100.2 nm with a standard deviation of 0.41 nm. Due to low lateral resolution of the optical microscope, a metrological atomic force microscope (AFM) was used to measure the 1D and 2D gratings. The period length of the 1D grating evaluated by using the fast Fourier transform (FFT) method was 2999.7 nm with a standard deviation of 0.36 nm. The FFT method was also expended for evaluation of the 2D grating. The calibrated value of 2D grating along the x- and y-axis were 3001.2 and 3000.7 nm with standard deviations of 0.73 and 0.64 nm, respectively. All the measurement results are traceable because the data was recorded by three stabilized laser interferometers embedded in the NMM.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.