Using optical deflection of cantilevers for alignment

Abstract

A calibration leveling system and method are provided which improve printing and imaging at the nanoscale including improved tip-based deposition and nanolithography. The system can include a scanning probe instrument having a video camera with an adjustable lens. The scanner can be coupled to a one or two dimensional array of cantilevers comprising cantilever tips for imaging or printing. The scanning probe instrument has one or more motors for controlling the scanner in the z-axis. The z-axis motors position the scanner so that the cantilever tips are in a level orientation relative to the surface of a substrate. Once the cantilever tips are level with the substrate, the positions of the z-axis motors can be recorded for future reference.

1 . A method comprising:
 providing a scanning probe instrument comprising a scanner operatively coupled to an array of tips for imaging or printing,   providing a flat substrate surface,
 wherein the position of the array of tips with respect to the substrate is controlled by three z-axis motors Z 1 , Z 2 , and Z 3  in a triangular, surrounding relationship with respect to the array, 
 wherein the Z 1 , Z 2 , and Z 3  motors are adapted to raise and lower the cantilever tips with respect to the surface, 
 wherein the Z 1  motor is also adapted to tilt the tips with respect to the substrate surface, and the Z 2  and Z 3  motors are adapted to level the tips with respect to the substrate surface, 
   lowering the array until at least some of the tips touch the surface,   adjust the Z 2  motor, the Z 3  motor, or both Z 2  and Z 3  motors, until all the tips are substantially level with respect to the substrate surface, and   record the relative positions of the z-axis motors for future calibration reference.   
     
     
         2 . The method according to  claim 1 , wherein the array of tips is a passive array. 
     
     
         3 . (canceled) 
     
     
         4 . The method according to  claim 1 , wherein the  tips are nanoscopic tips. 
     
     
         5 . (canceled) 
     
     
         6 . (canceled) 
     
     
         7 . The method according to  claim 1 , wherein an optical lens system is used to determine whether the tips are level. 
     
     
         8 . The method according to  claim 1 , wherein an optical lens system is used to determine whether the tips are level by observation of reflected light from the tips. 
     
     
         9 . The method according to  claim 1 , wherein lowering is carried out at increments of less than 5 microns until the tips touch the surface of the substrate. 
     
     
         10 . The method according to  claim 1 , further comprising the step of printing or imaging. 
     
     
         11 . The method according to  claim 1 , further comprising the step of printing by depositing material from a tip to a surface. 
     
     
         12 . The method according to  claim 1 , further comprising the step of printing or imaging with a single tip or an array comprising a plurality of tips. 
     
     
         13 . A method comprising:
 leveling an array of tips with respect to a substrate surface,   recording the level position for calibration,   printing or imaging with use of the level position for calibration.   
     
     
         14 . The method according to  claim 13 , wherein the leveling step is determined with an optical lens system. 
     
     
         15 . The method according to  claim 13 , wherein in the leveling step leveling is determined with an optical lens system wherein light is reflected from the tips. 
     
     
         16 . A method comprising:
 providing an instrument having one or more z-axis motors mounted to the instrument, for controlling a scanner operatively coupled to an array of tips for imaging or printing in the z-axis;   positioning the scanner until one or more tips touch a substrate;   determining the position of the tips on the surface of the substrate;   adjusting one or more z-axis motors to position the array so that each tip is in level contact with the substrate; and   recording the relative positions of the z-axis motors.   
     
     
         17 . A method comprising:
 providing a scanning probe instrument having one or more z-axis motors mounted to the scanning probe instrument, for controlling a scanner operatively coupled to an array of cantilevers comprising cantilever tips for imaging or printing in the z-axis;   lowering the scanner toward the surface of a sample holder a predetermined amount using a first z-axis motor;   focusing on the array using an optical lens system;   positioning the scanner until one or more cantilever tips touch a substrate;   determining the position of the cantilever tips on the surface of the substrate;   adjusting one or more z-axis motors to position the array of cantilevers so that each cantilever tip is in level contact with the substrate; and   recording the relative positions of the z-axis motors.   
     
     
         18 . The method as claimed in  claim 17 , wherein the scanning probe instrument further comprises:
 a video camera mounted to the scanning probe instrument;   a lens mounted on an adjustable collar attached to the scanning probe instrument;   a sample holder for holding a substrate;   one or more motors, mounted to the scanning probe instrument, for adjusting the sample holder in the x and y direction;   a motor for controlling a zoom function of the video camera; and   a motor for controlling a focus function of the video camera.   
     
     
         19 . The method as claimed in  claim 17 , wherein the lowering step further comprises:
 mounting a probe chip into the scanning probe instrument;   raising the lens to a predetermined height; and   zeroing out one or more z-axis motors.   
     
     
         20 . The method as claimed in  claim 17 , wherein the focusing step is performed by lowering the lens toward the surface of the sample holder. 
     
     
         21 . The method as claimed in  claim 17 , wherein the positioning step further comprises:
 inserting a substrate onto the sample holder;   lowering the array toward the substrate until the scanner is a predetermined distance from the substrate; and   lowering the array in predetermined increments until one or more cantilever tips touch the substrate.   
     
     
         22 . The method for performing calibration leveling as claimed in  claim 17 , wherein the video camera is used to determine the orientation of the cantilever tips on the surface of the substrate. 
     
     
         23 . A method comprising:
 providing a scanning probe instrument comprising a scanner operatively coupled to a one dimensional or two dimensional array of tips for imaging or printing;   providing a flat substrate surface,
 wherein the position of the array of tips with respect to the substrate is controlled by three z-axis motors Z 1 , Z 2 , and Z 3  in a triangular, surrounding relationship with respect to the array, 
 wherein the Z 1 , Z 2 , and Z 3  motors are adapted raise and lower the tips with respect to the surface, 
 wherein the Z 1  motor is also adapted to tilt the tips with respect to the substrate surface, and the Z 2  and Z 3  motors are adapted to level the tips with respect to the substrate surface, 
   lowering the array until at least some of the tips touch the surface,   adjust the Z 2  motor, the Z 3  motor, or both Z 2  and Z 3  motors, until all the tips are substantially level with respect to the substrate surface, wherein an optical lens system is used to determine whether the tips are level by observation of reflected light from the tips,   record the relative positions of the z-axis motors for future calibration reference.   
     
     
         24 . The method of  claim 23 , wherein the scanner is magnetically coupled. 
     
     
         25 . The method of  claim 23 , wherein the scanner is coupled to a two dimensional array.