Method for determining material interfacial and metrology information of a sample using atomic force microscopy
View Patent ↗A method for determining interfacial information and critical dimensions of a sample using atomic force microscopy. Tip-specimen deconvolution is performed on the scan lines before the critical dimension information processing. Local maxima and minima or local slope change of each scan line are found on a plurality of scan lines. A best fit line is then found for the plurality of maxim and minima or slope change points. Two best fit lines may be found using a plurality of maxima or minima or slope change points. An intersection of the two best fit lines can be used to determine a critical dimension such as a transition point. Such a method may be used to determine a track width of a trapezoidal magnetic write head or may be used to determine the location of a flare point on a magnetic write head.
1. A computer program, embodied on a computer readable medium, the program comprising, computer readable instructions for:
performing a scan of magnetic write pole, the scan including a plurality of scan lines;
performing a tip-sample deconvolution of the scan lines;
finding a local maxima or minima or slope change on four or more of the plurality of scan lines;
finding a first best fit line based on a first set of the maxima or minima or slope change;
finding a second best fit line based on a second set of the maxima or minima or slope change;
finding an intersection of the first and second best fit lines; and
determining interfacial information from the local maxima or minima or local slope change, the interfacial information indicating the location of an interface between different material of the sample.
2. A computer program as in claim 1 wherein the instructions for performing a scan of the write pole include instructions for using an atomic force microscope to perform a scan of the write pole.
3. A computer program as in claim 1 further comprising, instructions for producing a graphical model of the write pole, the graphical model including the critical dimension.
4. A computer program as in claim 1 further comprising, instructions for determining interfacial information from the local maxima and minima or local slope change and instructions for producing a graphical model of the write pole sample, the graphical model including interfacial information corresponding to the location of a trailing edge of the write pole.
5. A computer program as in claim 1 wherein the write pole comprises a magnetic write pole and a mask structure formed over the magnetic write pole, and wherein the interfacial information includes the location of an interface between the magnetic write pole and the mask structure.