Semiconductor constructions, methods of forming transistor gates, and methods of forming NAND cell units
View Patent ↗Some embodiments include methods of forming charge storage transistor gates and standard FET gates in which common processing is utilized for fabrication of at least some portions of the different types of gates. FET and charge storage transistor gate stacks may be formed. The gate stacks may each include a gate material, an insulative material, and a sacrificial material. The sacrificial material is removed from the FET and charge storage transistor gate stacks. The insulative material of the FET gate stacks is etched through. A conductive material is formed over the FET gate stacks and over the charge storage transistor gate stacks. The conductive material physically contacts the gate material of the FET gate stacks, and is separated from the gate material of the charge storage transistor gate stacks by the insulative material remaining in the charge storage transistor gate stacks. Some embodiments include gate structures.
1. A method of forming a NAND cell unit, comprising:
forming a select gate comprising a gate material and a dielectric material adjacent the gate material;
forming a string gate spaced from the select gate, the string gate comprising the gate material and the dielectric material adjacent the gate material; and
forming a conductive material directly contacting the gate material of the select gate and contacting the dielectric material of the string gate.
2. The method of claim 1 wherein the gate material comprises conductively-doped silicon, and wherein the conductive material comprises at least one metal.
3. The method of claim 1 wherein the conductive material contacts the gate material of the select gate.
4. The method of claim 1 wherein the conductive material has a thickness of from about 10 Å to about 150 Å.
5. The method of claim 1 wherein the conductive material has a thickness of from about 15 Å to about 50 Å.
6. The method of claim 1 wherein the conductive material does not contact the gate material of the string gate.
7. The method of claim 1 wherein the dielectric material comprises at least two discrete layers of dielectric material.
8. A method of forming a NAND cell unit, comprising:
forming a string gate comprising a gate material;
forming a select gate spaced from the string gate and comprising a gate material;
forming a peripheral gate spaced from the string gate and comprising a gate material;
forming a dielectric material adjacent each of the select, string, and peripheral gates;
etching through at least one of the dielectric materials adjacent each of the select, string, and peripheral gates;
providing a first conductive material through the at least one of the dielectric materials etched through, wherein the conductive material comprises a first conductive material; and
providing a second conductive material at least partially through the at least one of the dielectric materials etched through and over the first conductive material.
9. The method of claim 8 wherein the etching comprises etching through the dielectric material adjacent the select gate.
10. The method of claim 8 wherein the etching comprises etching through the dielectric material adjacent the peripheral gate.
11. The method of claim 8 wherein the etching comprises not etching through the dielectric material adjacent the string gate.
12. The method of claim 8 further comprising providing the first conductive material through the at least two of the dielectric materials.
13. A method of forming a NAND cell unit, comprising:
forming a string gate comprising a gate material;
forming a select gate spaced from the string gate and comprising a gate material;
forming a peripheral gate spaced from the string gate and comprising a gate material; and
providing conductive material directly contacting the string gate, the select gate, and the peripheral gate.
14. The method of claim 13 further comprising providing the conductive material contacting at least two of the gates.
15. The method of claim 13 wherein the conductive material comprises a first conductive material and further comprising providing a second conductive material contacting at least one of the gates.
16. The method of claim 13 wherein the conductive material comprises a first conductive material and further comprising providing a second conductive material contacting the at least one of the gates.
17. A method of forming a NAND cell unit, comprising:
forming a string gate comprising a gate material;
forming a select gate spaced from the string gate and comprising a gate material;
forming a peripheral gate spaced from the string gate and comprising a gate material;
forming a dielectric material adjacent each of the select, string and peripheral gates; and
etching through the dielectric material adjacent the peripheral gate.