Devices and systems with string drivers including high band gap material and methods of formation

Abstract

A device includes a string driver comprising a channel region between a drain region and a source region. At least one of the channel region, the drain region, and the source region comprises a high band gap material. A gate region is adjacent and spaced from the high band gap material. The string driver is configured for high-voltage operation in association with an array of charge storage devices (e.g., 2D NAND or 3D NAND). Additional devices and systems (e.g., non-volatile memory systems) including the string drivers are disclosed, as are methods of forming the string drivers.

1 . The device of  claim 3 , wherein the drain region and the source region comprise the high band gap material and the at least one channel region comprises the low band gap material. 
     
     
         2 . The device of  claim 1 , wherein the low band gap material is selected from the group consisting of germanium (Ge), silicon germanium (SiGe), and indium gallium arsenic (InGaAs). 
     
     
         3 . A device, comprising:
 an array of charge storage devices;   access lines in operable communication with the array of charge storage devices; and   a string driver in operable communication with at least one access line of the access lines, the string driver comprising:
 a drain region and a source region comprising a high band gap material; and 
 at least one channel region comprising:
 vertically oriented regions of the high band gap material and an additional high band gap material; or 
 a horizontally oriented region of either the high band gap material or a low band gap material, 
 
 the at least one channel region extending between the drain region and the source region. 
   
     
     
         4 . The device of  claim 3 , wherein:
 the array of charge storage devices is a three-dimensional NAND array comprising plurality of stacked tiers of the charge storage devices; and   the at least one channel region comprises the vertically oriented regions of the high band gap material and the additional high band gap material.   
     
     
         5 . The device of  claim 3 , wherein:
 the array of charge storage devices is a two-dimensional NAND array; and   the at least one channel region comprises the horizontally oriented region of either the high band gap material or the low band gap material.   
     
     
         6 . The device of  claim 3 , wherein the string driver further comprises a single gate region in association with at least one channel region extending between the drain region and the source region. 
     
     
         7 . The device of  claim 6 , wherein the single gate region of the string driver is associated with multiple channel regions of the at least one channel region. 
     
     
         8 . The device of  claim 3 , wherein:
 the source region comprises:
 the high band gap material doped with at least one dopant; and 
 the additional high band gap material doped with the at least one dopant; and 
   the drain region comprises:
 the high band gap material doped with the at least one dopant; and 
 the additional high band gap material doped with the at least one dopant, the at least one dopant selected from the group consisting of aluminum (Al) and silicon (Si). 
   
     
     
         9 . A system, comprising:
 an array of non-volatile memory devices;   at least one string driver in operable communication with the array, the string driver comprising a single gate region adjacent at least one channel region,   wherein:
 the single gate region circumscribes a high band gap material and an additional high band gap material of the at least one channel region; or 
 the single gate region is above the high band gap material or a low band gap material of the at least one channel region; and 
   at least one peripheral device in operable communication with the array of non-volatile memory devices, the at least one peripheral device comprising circuitry in operable communication with the at least one string driver.   
     
     
         10 . The system of  claim 9 , wherein the at least one string driver comprises a pillar portion comprising the high band gap material and the additional high band gap material of the at least one channel region, the pillar portion vertically extending from a substrate. 
     
     
         11 . The system of  claim 9 , wherein the at least one string driver comprises the single gate region above the high band gap material or the low band gap material of the at least one channel region, the at least one channel region laterally disposed between a source region and a drain region, the source region and the drain region comprising the high band gap material. 
     
     
         12 . (canceled) 
     
     
         13 . A method of forming a string driver, the method comprising:
 forming a high band gap material;   forming a dielectric material adjacent the high band gap material; and   forming a region of a conductive material adjacent the dielectric material, the region of the conductive material spaced from the high band gap material by at least the dielectric material.   
     
     
         14 . The method of  claim 13 , wherein forming the high band gap material comprises depositing the high band gap material at a temperature of less than 400° C. 
     
     
         15 . The method of  claim 13 :
 further comprising, before forming the high band gap material, forming another dielectric material; and   wherein forming the high band gap material comprises forming the high band gap material adjacent the other dielectric material.   
     
     
         16 . The method of  claim 13 , further comprising, before forming the dielectric material, doping portions of the high band gap material to form at least one drain region of doped high band gap material spaced from at least one source region of doped high band gap material by an undoped portion of the high band gap material or by an undoped portion of a low band gap material. 
     
     
         17 . The method of  claim 16 :
 further comprising, before forming the high band gap material:
 forming another conductive material; and 
 doping the other conductive material with at least one dopant; and 
   wherein forming a high band gap material comprises forming the high band gap material in physical contact with the other conductive material doped with the at least one dopant; and   wherein doping portions of the high band gap material comprises:
 exposing at least a lower portion of the high band gap material to heat to cause the at least one dopant to diffuse from the other conductive material into the lower portion of the high band gap material; and 
 implanting an additional amount of the at least one dopant into an upper portion of the high band gap material. 
   
     
     
         18 . The method of  claim 16 , wherein doping portions of the high band gap material comprises implanting at least one dopant into the portions of the high band gap material, the portions being laterally adjacent to the undoped portion of the high band gap material or to the undoped portion of the low band gap material. 
     
     
         19 . The method of  claim 13 , wherein:
 forming the region of the conductive material precedes forming the dielectric material and precedes forming the high band gap material;   forming the dielectric material comprises:   forming an opening through the conductive material; and   forming the dielectric material adjacent the conductive material exposed in the opening; and   forming the high band gap material comprises forming the high band gap material adjacent the dielectric material.   
     
     
         20 . The method of  claim 19 , further comprising forming another high band gap material along the high band gap material. 
     
     
         21 . The method of  claim 13 , wherein forming the dielectric material precedes forming the high band gap material, and forming the conductive material precedes forming the dielectric material, the dielectric material spacing the conductive material from the high band gap material. 
     
     
         22 . The method of  claim 13 , wherein forming the dielectric material follows forming the high band gap material, and forming the region of the conductive material follows forming the dielectric material.