Specific Process Knowledge/Characterization/AFM: Atomic Force Microscopy

Nanoman

Nanoman: positioned in cleanroom 4 - glass cage no. 4

The AFM: Nanoman is a product of Veeco Instruments. AFM stands for Atomic Force Microscope which is a scanning probe microscope where a sharp probe is scanned across a surface either in contact mode or tapping mode. The outcome is a topographic plot of the surface. It has a lateral solution of about 1 nm and a vertical resolution of less than 1 Å which makes it very suitable for topographic characterization in the nanometer regime. The limiting factor however is often the size of the probe in use. The tip radius of curvature (ROC) can be from 2 nm up to more than 20 nm depending on the chosen probe. The half cone angle of the tip can vary from less than 3^o to over 25^o giving problems resolving high aspect ratio structures.

The main purposes are surface roughness measurements and step/structure high measurements in the nanometer and sub-micrometer regime. For larger structure see the topografic measurement page.

To get some product information from the vendor take a look at Veeco's homepage [1]

A rough overview of the performance of the AFM: Nanoman

Purpose	Topografic measurement in the nanometer and and sub-micrometer regime	Surface roughness measurement Step/structure hight measurement Surface image
Performance	Scan range xy	Up to 90 µm square
.	Scan range z	1 µm (can go up to 6µm with special settings)
.	Resolution xy	Down to 1.4 nm - accuracy better than 2%
.	Resolution z	<1 Å - accuracy better than 2%
.	Max. scan depth as a function of trench width W	~1 for our standard probe. Can be improved to about 10 with the right probe
Hardware settings	Tip radius of curvature	Standrad probe: <12 nm
Substrates	Substrate size	Up to 6"
.	Substrate material allowed	In principle all materials