Development Testing of a XYZ Scanner for Atomic Force Microscope

Atomic force microscopy (AFM) is a widely used tool in nano measurement and manipulation techniques. However, a traditional AFM system suffers from the limitation of slow  scanning  rate,  due  to  the  low  dynamic  performance  of 
piezoelectric positioners. As an important part of AFM system, scanner  will  have  a  significant  impact  the  result  of  the  scanning  imaging  and  operation.  It  is  well  know  that  high-speed operation of anAFM are increasingly required, and it is also a challenge  for  the  researchers.  In  this  paper,  we  proposed  a parallel  kinematic  high-speed  piezoelectric  actuator  (PZT) XYZ scanner. The design is aimed at achieving high resonance frequencies and low cross-coupling. The developed stage consists  of  a  parallel kinematic  XY stage  and  a  Z  stage.  The  Z stage  is mounted  on  the  central  moving  platform  of  the  XY stage.  To  achieve  the  design  objective,  several  parallel  leaf flexure  hinge  mechanisms,  arranging  symmetrically  around the  central  moving  platform  of  the  XY  stage,  are  utilized  to provide  large  stiffness  and  reduce  cross-coupling.  For  the  Z stage, a symmetrical leaf flexure  parallelogram  mechanism is adopted to achieve high resonance frequencies and decoupling. Then,  finite  element  analysis  (FEA)  is  utilized  to  validate  the 
characteristics  of  the  XYZ  scanner.  Finally,  extensive  experiments are conducted, demonstrating feasibility of the proposed scanner.