Ellipsometry system for measuring molecular binding, adsorption and desorption

Abstract

According to one aspect of the invention, there is provided an ellipsometry system for measuring any one or more of molecular binding, adsorption and desorption on a substrate, the system comprising: a) a cuvette comprising i) a body within which a cavity is formed and an opening on the body, wherein the cavity extends into the opening through which the substrate is immersed; ii) a window formed on each of two oppositely located walls of the body, wherein the windows are aligned to allow light to enter through one of the two windows to reflect off the portion of the substrate immersed in the cavity and exit through the other of the two windows; iii) a channel arrangement enclosed within the body of the cuvette and comprising two non-contiguous portions, wherein one of the two non-contiguous portions guides fluid into the cavity and the other non-contiguous portion guides fluid out of the cavity; b) a polarized light source disposed to provide the light that enters into one of the two windows on the body of the cuvette; and c) a detection stage disposed to receive the light that exits through the other of the two windows on the body of the cuvette, wherein the detection stage is configured to measure polarization rotation of the received light, the polarization rotation caused by any one or more of molecular binding, adsorption and desorption occurring on the substrate surface. The detection stage preferably contains a polarisation modulator, which is configured to measure polarization rotation of the received light.

1 . An ellipsometry system for measuring any one or more of molecular binding, adsorption and desorption on a substrate, the system comprising:
 (a) a cuvette comprising
 (i) a body within which a cavity is formed and an opening on the body, wherein the cavity extends into the opening through which the substrate is immersed; 
 (ii) a window formed on each of two oppositely located walls of the body, wherein the windows are aligned to allow light to enter through one of the two windows to reflect off the portion of the substrate immersed in the cavity and exit through the other of the two windows; 
 (iii) a channel arrangement enclosed within the body of the cuvette and comprising two non-contiguous portions, wherein one of the two non-contiguous portions guides fluid into the cavity and the other non-contiguous portion guides fluid out of the cavity, wherein the cuvette further comprises a fluid inlet and a fluid outlet formed on the body, and wherein the fluid inlet and the fluid outlet are in fluid communication with the channel arrangement; 
   (b) a polarized light source disposed to provide the light that enters into one of the two windows on the body of the cuvette; and   (c) a detection stage disposed to receive the light that exits through the other of the two windows on the body of the cuvette, wherein the detection stage is configured to measure polarization rotation of the received light, the polarization rotation caused by any one or more of molecular binding, adsorption and desorption occurring on the substrate surface.   
     
     
         2 . (canceled) 
     
     
         3 . The ellipsometry system of  claim 1 , wherein the channel arrangement comprises:
 (a) an input conduit that is coupled at one end to the fluid inlet and coupled to the cavity at the other end; and   (b) an output conduit that is coupled at one end to the fluid outlet and coupled to the cavity at the other end.   
     
     
         4 . The ellipsometry system of  claim 3  wherein the input conduit extends into the cavity by going around a segment of the portion of the substrate immersed in the cavity. 
     
     
         5 . The ellipsometry system of  claim 3 , wherein the input conduit comprises two branches, wherein each of the two branches has one end that meets at a common region for coupling to the fluid inlet and the other end is coupled to opposite corners of the cavity. 
     
     
         6 . The ellipsometry system of  claim 3 , wherein the cuvette further comprises a support structure adapted to hold the substrate with at least a portion immersed in the cavity. 
     
     
         7 . The ellipsometry system of  claim 6 , wherein the support structure has a surface that receives the substrate and an opposite surface that faces the input conduit of the channel arrangement. 
     
     
         8 . The ellipsometry system of  claim 7 , wherein the support structure comprises a biasing element that urges the substrate against the receiving surface of the support structure. 
     
     
         9 . The ellipsometry system of  claim 8 , wherein the biasing element comprises any one or more of a leaf, a screw and a clip. 
     
     
         10 . The ellipsometry system of  claim 1 , further comprising a pump coupled to the fluid outlet of the body of the cuvette. 
     
     
         11 . The ellipsometry system of  claim 1 , wherein the body of the cuvette further comprises a reagent inlet that extends into the channel arrangement which is in fluid communication with the fluid inlet. 
     
     
         12 . The ellipsometry system of  claim 1 , wherein the opening, the fluid inlet and the fluid outlet are located on different surfaces of the body of the cuvette. 
     
     
         13 - 20 . (canceled)