Method and system for measuring bumps based on phase and amplitude information

A method for measuring a height of a microscopic structure, the method comprises:

• receiving or generating information that comprises amplitude information and phase information, wherein the information is indicative of a shape and a size of the microscopic structure;
• thresholding pixels of the amplitude information to provide a mask that comprises masked amplitude pixels;
• applying the mask on the phase information to provide masked phase pixels;
• selecting, out of the masked phase pixels, selected phase pixels that correspond to a phase criterion, the selected phase pixels have selected phase pixels attribute values;
• finding, out of the phase information, elected phase pixels that have the selected phase pixel attribute values;
• and
• generating a height measurement result based the elected phase pixels.

A device for measuring a height of a microscopic structure, the device comprises:

• a storage circuit for storing a phase image and an amplitude image of the microscopic structure;
• a reminder height calculation circuit arranged to calculate reminder height estimates based on the phase image pixels;
• a feature extractor arranged to detect an edge of the microscopic structure on a surface of an object;
• a size attribute circuit arranged to calculate a size attribute of the microscopic structure based on a size of a shape defined by the edge of the microscopic structure;
• a selection circuit arranged to select a selected height range out multiple height ranges based upon the size attribute of the microscopic structure and an allowable relationship between the size attribute and height values of the microscopic structure;
• and
• and a height calculation circuit arranged to calculate an actual height of the microscopic structure based on the selected height range and the reminder height estimate.

A method for measuring a height of a microscopic structure, the method comprises:

• generating or receiving a phase image and an amplitude image of the microscopic structure;
• calculating reminder height estimates based on the phase image pixels;
• detecting the edge of the microscopic structure on a surface of an object;
• calculating size attribute of the microscopic structure based on a size of a shape defined by the edge of the microscopic structure;
• selecting a selected height range out multiple height ranges based upon the size attribute of the microscopic structure and an allowable relationship between the size attribute and height values of the microscopic structure;
• and
• calculating an actual height of the microscopic structure based on the selected height range and the reminder height estimate.