Charge trapping dielectric structures with variable band-gaps

A method of forming a dielectric structure on a surface of a substrate, the method comprising:

• forming a first material such that the first material is a dielectric material disposed on and contacting a region, on the substrate, operable to conduct current, the first material having a first band-gap value, a first dielectric constant value, and a first thickness, the first dielectric constant value being greater than twice a value of dielectric constant of silicon dioxide, the first material including an insulating carbon compound;
• forming a second material disposed on and contacting the first material by nitridation of a surface of the first material such that the second material consists essentially of a dielectric nitride of the first material, the second material disposed to operatively trap charge carriers from the first material, the second material having a second band-gap value, a second dielectric constant, and a second thickness, the second band-gap value being less than the first band-gap value;
• forming a third material on and contacting the second material, the third material being a dielectric, the third material having a third band-gap value, a third dielectric constant value, and a third thickness, the third band-gap value being greater than the first band-gap value;
• and
• forming a conductive layer on and contacting the third material, the conductive layer conductively coupled to a structure on the substrate separate from the dielectric structure.

A method of forming a semiconductive device, the method comprising:

• forming a memory array in a substrate including:
• forming at least one dielectric structure containing at least nitrogen in a charge trapping region in an integrated circuit such that forming the at least one dielectric structure includes:
• forming a first portion disposed above the surface of the substrate such that the first portion is a dielectric material disposed on and contacting a device region operable to conduct current in the integrated circuit, the first portion having a composition with a first band-gap value, the composition being a carbon compound or a metal oxide;
• forming a second portion disposed on and contacting the first portion by nitridation of a surface of the composition of the first portion such that the second portion consists essentially of a dielectric nitride of the composition, the second portion formed as the charge trapping region having a composition to trap charge carriers, the composition of the second portion having a band-gap value less than the first band-gap value;
• and
• forming a third portion disposed on and contacting the second portion, the third portion having a second band-gap value, the second band-gap value being greater than the first band-gap value, the third portion being a dielectric;
• and
• depositing a conductive material on and contacting the at least one dielectric structure, the conductive layer conductively coupled to a structure on the substrate separate from the at least one dielectric structure;
• and
• forming an address decoder in the substrate, the address decoder coupled to the memory array.