Method for forming thin film heads using a bi-layer anti-reflection coating for photolithographic applications and a device thereof

Abstract

A bi-layer anti-reflective coating for use in photolithographic applications, and specifically, for use in ultraviolet photolithographic processes. The bi-layered anti-reflective coating is used to minimize pattern distortion due to reflections from neighboring features in the construction of microcircuits. The bi-layer anti-reflection coating features a first layer, an absorption layer, disposed on a second layer, a dielectric layer, which is then disposed between a substrate and a photoresist layer. The dielectric/absorption layer comprises one combination selected from Ta/Al 2 O 3 , Ta/SiO 2 , Ta/TiO 2 , Ta/Ta 2 O 5 , Ta/Cr 2 O 3 , Ta/Si 3 N 4 , Ti/Al 2 O 3 , Ti/SiO 2 , Ti/TiO 2 , Ti/Ta 2 O 5 , Ti/Cr 2 O 3 , Ti/Si 3 N 4 , Cr/Al 2 O 3 , Cr/SiO 2 , Cr/TiO 2 , Cr/Ta 2 O 5 , Cr/Cr 2 O 3 , Cr/Si 3 N 4 , Al/Al 2 O 3 , Al/TiO 2 , Al/Ta 2 O 5 , Al/Cr 2 O 3 , Al/Si 3 N 4 , Ni/Al 2 O 3 , Ni/SiO 2 , Ni/TiO 2 , Ni/Ta 2 O 5 , Ni/Cr 2 O 3 , Ni/Si 3 N 4 , Ir/Al 2 O 3 , Ir/SiO 2 , Ir/TiO 2 , Ir/Ta 2 O 5 , Ir/Cr 2 O 3 , and Ir/Si 3 N 4 . At least the absorption and dielectric layers can be formed using vacuum deposition. A unique character of the bi-layer anti-reflective coatings is that it allows a thinner anti-reflection layer that has a wider process latitude.

1 . A method for forming a bi-layer anti-reflective coating for minimizing pattern distortion in photolithography, comprising:
 forming a dielectric layer on a surface; and   forming an absorption layer on the dielectric layer, wherein the absorption layer and dielectric layer are conformal to the surface, and wherein the dielectric/absorption layer comprises one combination selected from Ta/Al 2 O 3 , Ta/SiO 2 , Ta/TiO 2 , Ta/Ta 2 O 5 , Ta/Cr 2 O 3 , Ta/Si 3 N 4 , Ti/Al 2 O 3 , Ti/SiO 2 , Ti/TiO 2 , Ti/Ta 2 O 5 , Ti/Cr 2 O 3 , Ti/Si 3 N 4 , Cr/Al 2 O 3 , Cr/SiO 2 , Cr/TiO 2 , Cr/Ta 2 O 5 , Cr/Cr 2 O 3 , Cr/Si 3 N 4 , Al/Al 2 O 3 , Al/TiO 2 , Al/Ta 2 O 5 , Al/Cr 2 O 3 , Al/Si 3 N 4 , Ni/Al 2 O 3 , Ni/SiO 2 , Ni/TiO 2 , Ni/Ta 2 O 5 , Ni/Cr 2 O 3 , Ni/Si 3 N 4 , Ir/Al 2 O 3 , Ir/SiO 2 , Ir/TiO 2 , Ir/Ta 2 O 5 , Ir/Cr 2 O 3 , and Ir/Si 3 N 4 .   
     
     
         2 . The method of  claim 1  wherein the forming of the dielectric and absorption layers further comprises forming the dielectric layer with a first thickness and forming the absorption layer with a second thickness. 
     
     
         3 . The method of  claim 1  wherein the forming the dielectric layer further comprises depositing a dielectric having substantially zero absorption for a predetermined wavelength. 
     
     
         4 . The method of  claim 1  wherein the forming the absorption layer further comprises depositing an absorbing material having an extinction coefficient (k) not equal to zero for a predetermined wavelength. 
     
     
         5 . The method of  claim 1  wherein the forming of the dielectric and absorption layers is accomplished by a vacuum deposition process. 
     
     
         6 . The method of  claim 5  wherein the vacuum deposition process further comprises at least one of chemical vapor deposition, physical vapor deposition and ion beam deposition. 
     
     
         7 . The method of  claim 1  wherein forming the absorption layer on the dielectric layer comprises forming a bottom anti-reflective coating. 
     
     
         8 . The method of  claim 1  wherein forming the absorption layer on the dielectric layer further comprises determining a thickness of the dielectric layer and the absorption layer to optimize an anti-reflection property of the combined dielectric and absorption layers. 
     
     
         9 . The method of  claim 8  wherein determining the thickness of the dielectric layer and the absorption layer yields a wider process latitude. 
     
     
         10 . The method of  claim 1  further comprising forming a photoresist layer on the absorption layer. 
     
     
         11 . The method of  claim 1 , wherein forming an absorption layer and dielectric layer further comprises fully absorbing light in the absorption layer and/or the dielectric layer. 
     
     
         12 . The method of  claim 1  further comprises forming features on the surface, wherein the absorption layer and dielectric layer are formed conformally over the features. 
     
     
         13 . The method of  claim 12  further comprises fully absorbing light reflected off the surface and the features formed on the surface by the absorption layer and/or the dielectric layer. 
     
     
         14 . A storage device, comprising:
 at least one data storage medium mounted for simultaneous rotation about an axis;   at least one magnetic head mounted on an actuator assembly for reading and writing data on the at least one data storage medium; and   an actuator motor for moving the at least one magnetic head relative to the at least one data storage medium; and   wherein the head is formed using a photoresist process and wherein at least one stage in the photoresist process includes forming a bi-layer anti-reflective coating for minimizing pattern distortion in photolithography, the forming the bi-layer anti-reflective coating comprising:   forming a dielectric layer on a surface; and   forming an absorption layer on the dielectric layer, wherein the absorption layer and dielectric layer are conformal to the surface and wherein the dielectric/absorption layer comprises one combination selected from Ta/Al 2 O 3 , Ta/SiO 2 , Ta/TiO 2 , Ta/Ta 2 O 5 , Ta/Cr 2 O 3 , Ta/Si 3 N 4 , Ti/Al 2 O 3 , Ti/SiO 2 , Ti/TiO 2 , Ti/Ta 2 O 5 , Ti/Cr 2 O 3 , Ti/Si 3 N 4 , Cr/Al 2 O 3 , Cr/SiO 2 , Cr/TiO 2 , Cr/Ta 2 O 5 , Cr/Cr 2 O 3 , Cr/Si 3 N 4 , Al/Al 2   0   3 , Al/TiO 2 , Al/Ta 2 O 5 , Al/Cr 2 O 3 , Al/Si 3 N 4 , Ni/Al 2 O 3 , Ni/SiO 2 , Ni/TiO 2 , Ni/Ta 2 O 5 , Ni/Cr 2 O 3 , Ni/Si 3 N 4 , Ir/Al 2 O 3 , Ir/SiO 2 , Ir/TiO 2 , Ir/Ta 2 O 5 , Ir/Cr 2 O 3 , and Ir/Si 3 N 4 .