Dispersing immersion liquid for high resolution imaging and lithography

Abstract

Methods and apparatus are described for delivering index-matching immersion liquid in high numerical-aperture optical microscopy and lithography. An array of immersion liquid droplets is delivered to a specimen substrate or specimen substrate cover by an immersion liquid printing apparatus. An immersion liquid reservoir provides immersion liquid to the printer by a precision pump. The printer delivers immersion liquid to the substrate or substrate cover in arrays of immersion liquid droplets of defined volumes and array patterns. The volumes and patterns of array droplets delivered to the substrate or substrate cover are optimized to maintain adequate immersion liquid between the substrate or substrate cover and an immersion objective while avoiding the formation of air bubbles in the immersion liquid and the accumulation of excess volumes of immersion liquid.

1 . A method for preparing a specimen substrate, comprising:
 printing an array of droplets onto the substrate;   positioning the array of droplets relative to a specimen; and   contacting an objective to a selected one of the droplets, wherein the droplets comprise a substance having a high refractive index.   
   
   
       2 . The method of  claim 1 , wherein the substance includes a gel. 
   
   
       3 . The method of  claim 1 , wherein the substance includes a liquid. 
   
   
       4 . The method of  claim 3 , wherein the liquid includes water. 
   
   
       5 . The method of  claim 3 , wherein the liquid includes glycerol. 
   
   
       6 . The method of  claim 3 , wherein the liquid includes oil. 
   
   
       7 . The method of  claim 1 , wherein the objective is an objective of a microscope. 
   
   
       8 . The method of  claim 7 , wherein the step of printing includes shaping the array of droplets. 
   
   
       9 . The method of  claim 8 , wherein shaping the array of droplets optimizes a scan area of the microscope. 
   
   
       10 . The method of  claim 8 , wherein shaping the array of droplets optimizes a scanning pattern of the microscope. 
   
   
       11 . The method of  claim 8 , wherein shaping the array of droplets is based on surface tension characteristics of the liquid. 
   
   
       12 . The method of  claim 8 , wherein the substance includes a liquid and shaping the array of droplets is based on surface tension characteristics of the liquid. 
   
   
       13 . The method of  claim 8 , wherein printing an array of droplets includes dispensing a liquid through ducts and wherein shaping the array of droplets includes selecting a shape of a duct. 
   
   
       14 . The method of  claim 7 , wherein the microscope is an inverted imaging instrument. 
   
   
       15 . The method of  claim 1 , wherein the substrate comprises a microscope slide. 
   
   
       16 . The method of  claim 1 , wherein the substrate comprises a multi-well plate. 
   
   
       17 . A microscopy system comprising
 an immersion objective configured to be positioned in contact with one or more drops of a high refractive index liquid; and   a printer configured to print an array of drops of the liquid on to a surface of a substrate, wherein one or more of the array of drops are arranged to provide an interface between a specimen carried by the substrate and the immersion objective.   
   
   
       18 . The system of  claim 17 , wherein the one or more drops provide high refractive index interfaces for the immersion objective of a microscope. 
   
   
       19 . The system of  claim 18 , wherein the printer includes an ultrasonic nebulizer for dispersing the liquid, thereby forming the array of drops. 
   
   
       20 . The system of  claim 18 , wherein the printer includes a piezoelectric element includes an ultrasonic nebulizer for dispersing the liquid, thereby forming the array of drops. 
   
   
       21 . The system of  claim 18 , wherein the liquid includes water. 
   
   
       22 . The system of  claim 18 , wherein the liquid includes glycerol. 
   
   
       23 . The system of  claim 18 , wherein the liquid includes oil.