Methods for forming structures by generation of isolated graphene layers having a reduced dimension

Abstract

Graphite-based devices with a reduced characteristic dimension and methods for forming such devices are provided. One or more thin films are deposited onto a substrate and undesired portions of the deposited thin film or thin films are removed to produce processed elements with reduced characteristic dimensions. Graphene layers are generated on selected processed elements or exposed portions of the substrate after removal of the processed elements. Multiple sets of graphene layers can be generated, each with a different physical characteristic, thereby producing a graphite-based device with multiple functionalities in the same device.

What is claimed is: 
     
         1 . A method of forming a graphite-based structure on a patterned substrate, the patterned substrate comprising a plurality of initial elements and a plurality of initial trenches, wherein each respective initial element in the plurality of initial elements is separated from an adjacent initial element in the plurality of initial elements by a corresponding initial trench in the plurality of initial trenches, the method comprising:
 (A) protecting the patterned substrate with a first protective mask, the first protective mask comprising a first plurality of isolated openings, wherein the first plurality of isolated openings is characterized by a first opening width that does not exceed (a) a minimum initial element width of the plurality of initial elements or (b) a minimum initial trench width of the plurality of initial trenches;   (B) depositing a first material through the first plurality of isolated openings in the first protective mask, thereby producing a first plurality of processed elements on the patterned substrate, wherein the first plurality of processed elements has a first reduced width that corresponds to the first opening width of the first protective mask and does not exceed (a) the minimum initial element width or (b) the minimum initial trench width;   (C) protecting the first plurality of processed elements on the patterned substrate with a second protective mask, the second protective mask comprising a second plurality of isolated openings, wherein the second plurality of isolated openings is characterized by a second opening width that does not exceed (a) the minimum initial element width or (b) the minimum initial trench width;   (D) depositing a second material through the second plurality of isolated openings in the second protective mask, thereby producing a second plurality of processed elements on the patterned substrate, wherein the second plurality of processed elements has a second reduced width that corresponds to the second opening width of the second protective mask and does not exceed (a) the minimum initial element width or (b) the minimum initial trench width; and   (E) generating, concurrently or sequentially, first and second pluralities of graphene layers, wherein each respective graphene layer in the first plurality of graphene layers is generated on a top surface of a corresponding processed element in the first plurality of processed elements and each respective graphene layer in the second plurality of graphene layers is generated on a top surface of a corresponding processed element in the second plurality of processed elements thereby producing said graphite-based structure with isolated graphene layers having the first and second reduced widths.   
     
     
         2 . The method of  claim 1 , wherein
 the plurality of initial elements comprises a first subset of initial elements and a second subset of initial elements, wherein the second subset of initial elements does not overlap with the first subset of initial elements;   each respective processed element in the first plurality of processed elements is deposited on a side wall of a corresponding initial element in the first subset of initial elements; and   each respective processed element in the second plurality of processed elements is deposited on a side wall of a corresponding initial element in the second subset of initial elements.   
     
     
         3 . The method of  claim 2 , wherein the first subset of initial elements and the second subset of initial elements do not form an interdigital pattern. 
     
     
         4 . The method of  claim 2 , wherein the first subset of initial elements is present in one portion of the substrate and the second subset of initial elements is present in another portion of the substrate. 
     
     
         5 . The method of  claim 1 , wherein
 the plurality of initial elements comprises a first subset of initial elements and a non-overlapping second subset of initial elements, wherein the first subset of initial elements and the second subset of initial elements form an interdigital pattern;   each respective processed element in the first plurality of processed elements is deposited on a side wall of a corresponding initial element in the first subset of initial elements; and   each respective processed element in the second plurality of processed elements is deposited on a side wall of a corresponding initial element in the second subset of initial elements.   
     
     
         6 . The method of  claim 1 , wherein
 each initial element in the plurality of initial elements comprises first and second side walls;   each respective processed element in the first plurality of processed elements is deposited on the first side wall of a corresponding initial element in the plurality of initial elements; and   each respective processed element in the second plurality of processed elements is deposited on the second side wall of the same corresponding initial element in the plurality of initial elements.   
     
     
         7 . The method of  claim 1 , wherein the first material or the second material comprises a foundation material. 
     
     
         8 . The method of  claim 1 , wherein the first material is the same as the second material. 
     
     
         9 . The method of  claim 1 , wherein the first material is different than the second material. 
     
     
         10 . The method of  claim 1 , wherein the first material comprises nickel (Ni) and the second material comprises copper (Cu). 
     
     
         11 . The method of  claim 1 , wherein the first reduced width is the same as the second reduced width. 
     
     
         12 . The method of  claim 1 , wherein the first reduced width is different than the second reduced width. 
     
     
         13 . The method of  claim 1 , wherein the first reduced width or the second reduced width is between 2 nm and 100 nm. 
     
     
         14 . The method of  claim 1 , wherein each graphene layer in the first or second plurality of graphene layers consists of between 1 and 50 graphene sheets. 
     
     
         15 . The method of  claim 1 , wherein each graphene layer in the first or second plurality of graphene layers consists of between 50 and 100 graphene sheets. 
     
     
         16 . The method of  claim 1 , wherein each graphene layer in the first or second plurality of graphene layers consists of between 100 and 500 graphene sheets. 
     
     
         17 . The method of  claim 1 , wherein each graphene layer in the first plurality of graphene layers consists of between 5 and 20 graphene sheets, and each graphene layer in the second plurality of graphene layers consists of between 1-5 graphene sheets. 
     
     
         18 . A method of forming a graphite-based structure on a substrate, the method comprising:
 (A) patterning the substrate to form a plurality of initial elements and a plurality of initial trenches, wherein
 (i) each respective initial element in the plurality of initial elements is separated from an adjacent initial element in the plurality of initial elements by a corresponding initial trench in the plurality of initial trenches, 
 (ii) each initial element in the plurality of initial elements comprises at least a first level and a second level, wherein the second level is wider than the first level, thus forming a protrusion, and 
 (iii) each initial trench in the plurality of initial trenches comprises at least a first level and a second level that correspond to the first and second levels of adjacent initial elements in the plurality of initial elements; 
   (B) backfilling up to the second level of each trench in the plurality of initial trenches with a backfill material;   (C) conformally depositing, subsequent to the backfilling, a first material on the patterned substrate, thereby producing a first thin film on the backfilled material, wherein the first thin film is characterized by a first thickness that does not exceed a minimum protrusion width;   (D) anisotropically etching the substrate to remove other portions of the first thin film while retaining portions of the first thin film overlaid on side walls of the first levels of the plurality of initial elements, thereby producing a first plurality of processed elements, wherein
 (i) each respective processed element in the first plurality of processed elements is defined by a retained portion of the first thin film on a side wall of the first level of a corresponding initial element in the plurality of initial elements, and 
 (ii) the first plurality of processed elements has a first reduced width that corresponds to the first thickness of the first thin film and does not exceed the minimum protrusion width; 
   (E) removing the backfill material by selectively etching the substrate, thereby exposing the second level of each initial trench in the plurality of initial trenches;   (F) conformally depositing, subsequently to the removing the backfill material, a second material on the patterned substrate, thereby producing a second thin film on the substrate, wherein the second thin film is characterized by a second thickness that does not exceed (a) the minimum protrusion width or (b) a minimum initial trench width;   (G) anisotropically etching the substrate to remove other portions of the second thin film while retaining portions of the second thin film overlaid on side walls of the first plurality of processed elements and on side walls of the second levels of the plurality of initial elements, thereby producing second and third pluralities of processed elements, wherein
 (i) each respective processed element in the second plurality of processed elements is defined by a retained portion of the second thin film on a side wall of a corresponding processed element in the first plurality of processed elements, 
 (ii) each respective processed element in the third plurality of processed elements is defined by a retained portion of the second thin film on a side wall of the second level of a corresponding initial element in the plurality of initial elements, and 
 (iii) the second and third pluralities of processed elements have a second reduced width that corresponds to the second thickness of the second thin film and does not exceed (a) the minimum protrusion width or (b) the minimum initial trench width; and 
   (H) generating, concurrently or sequentially, first, second and third pluralities of graphene layers, wherein each respective graphene layer in the first, second or third pluralities of graphene layers is generated on a top surface of a corresponding processed element in the first, second, and third pluralities of processed elements, respectively, thereby producing said graphite-based structure with isolated graphene layers having the first and second reduced widths.   
     
     
         19 . A method of forming a graphite-based structure on a substrate, the method comprising:
 (A) patterning the substrate to form a first level of each initial element in a plurality of initial elements and a first level of each initial trench in a plurality of initial trenches, wherein the first level of each respective initial element in the plurality of initial elements is separated from the first level of an adjacent initial element in the plurality of initial elements by the first level of a corresponding initial trench in the plurality of initial trenches;   (B) conformally depositing a first material on the patterned substrate, thereby producing a first thin film overlaying the patterned substrate, wherein the first thin film is characterized by a first thickness that does not exceed (a) an minimum initial element width of the plurality of initial elements or (b) half of a minimum initial trench width of the plurality of initial trenches;   (C) anisotropically etching the substrate to remove other portions of the first thin film while retaining portions of the first thin film overlaid on side walls of the first levels of the plurality of initial elements, thereby producing a first plurality of processed elements, wherein
 (i) each respective processed element in the first plurality of processed elements is defined by a retained portion of the first thin film on a side wall of the first level of a corresponding initial element in the plurality of initial elements, and 
 (ii) the first plurality of processed elements has a first reduced width that corresponds to the first thickness of the first thin film and does not exceed (a) the minimum initial element width or (b) half of the minimum initial trench width; 
   (D) patterning, subsequently to the removing portions of the first thin film, the substrate to form a second level of each initial element in the plurality of initial elements and a second level of each initial trench in a plurality of initial trenches, wherein the second level of each initial element has a width different than the first level of the same initial element, thereby forming a protrusion;   (E) conformally depositing a second material on the patterned substrate, thereby producing a second thin film on the substrate, wherein the second thin film is characterized by a second thickness that does not exceed (a) a minimum protrusion width or (b) half of the minimum initial trench width;   (F) anisotropically etching the substrate to remove other portions of the second thin film while retaining portions of the second thin film overlaid on side walls of the first plurality of processed elements and on side walls of the second levels of the plurality of initial elements, thereby producing second and third pluralities of processed elements, wherein
 (i) each respective processed element in the second plurality of processed elements is defined by a retained portion of the second thin film on a side wall of a corresponding processed element in the first plurality of processed elements, 
 (ii) each respective processed element in the third plurality of processed elements is defined by a retained portion of the second thin film on a side wall of the second level of a corresponding initial element in the plurality of initial elements, and 
 (iii) the second and third pluralities of processed elements have a second reduced width that corresponds to the second thickness of the second thin film and does not exceed (a) the minimum protrusion width or (b) half of the minimum initial trench width; and 
   (G) generating, concurrently or sequentially, first, second and third pluralities of graphene layers, wherein each respective graphene layer in the first, second or third pluralities of graphene layers is generated on a top surface of a corresponding processed element in the first, second, and third pluralities of processed elements, respectively, thereby producing said refined graphite-based structure with isolated graphene layers having the first and second reduced widths.   
     
     
         20 . The method of  claim 19 , wherein the patterning the substrate to form the second level of each initial element in the plurality of initial elements comprises depositing the second level on the first level of each initial element in the plurality of initial elements, thereby producing the second level on top of the first level.