Characterizing Dimensions of Structures Via Scanning Probe Microscopy

Abstract

A method comprising characterizing the dimensions of structures on a semiconductor device having dimensions less than approximately 100 nanometers (nm) using one of scanning probe microscopy (SPM) or profilometry.

1 . A method of characterizing a set of structures on a semiconductor device, comprising:
 establishing a reference position on the device using one of scanning probe microscopy (SPM) or profilometry; and   characterizing the set of structures by repeatedly performing the method comprising:
 establishing a target position on an upper surface of one of the set of structures using the one of SPM or profilometry, said upper surface being located further away from the device than the location of the reference position; and 
 determining a difference between the reference position and the target position, the difference defining a physical height of the structure; 
   wherein the reference position and the portion of the device coupled to the structure are coplanar;   further wherein the reference position is at a dummy active and the target position is at a SRAM field oxide.   
     
     
         2 . The method of  claim 1  wherein using SPM comprises using a technique selected from a group consisting of atomic force microscopy (AFM), scanning tunneling microscopy (STM), and near-field scanning optical microscopy (NSOM). 
     
     
         3 . The method of  claim 1  wherein establishing the target position on the upper surface of the one of the set of structures comprises using a structure having dimensions between approximately 0.2 nanometers and 100 nanometers. 
     
     
         4 . The method of  claim 1  wherein establishing the reference position comprises determining an average of measurements at multiple positions on a single plane. 
     
     
         5 . The method of  claim 1  wherein establishing the target position on the upper surface of the one of the set of structures comprises using a structure selected from a group consisting of static random access memory (SRAM) arrays, dynamic random access memory (DRAM) arrays, inductors, input/output structures, and combinations thereof. 
     
     
         6 . The method of  claim 1  wherein determining the difference occurs in less than or equal to approximately twenty seconds. 
     
     
         7 . The method of  claim 1  wherein determining the difference comprises determining step height in a static random access memory (SRAM) array. 
     
     
         8 . The method of  claim 1  wherein the reference position comprises any position having dimensions that permit access by a probe of the one of SPM or profilometry. 
     
     
         9 . The method of  claim 1  wherein the reference position is at a dummy active and the target position is at a SRAM field oxide. 
     
     
         10 . The method of  claim 1  wherein a space between a first of the one of the set of structures and a second of the one of the set of structures is less than a width of a probe of the one of SPM or profilometry. 
     
     
         11 . The method of  claim 1  wherein a probe of the one of SPM or profilometry scans the upper surface of each of the set of structures without the probe lifting off the upper surface of the each of the set of structures.