Integrated assemblies having thicker semiconductor material along one region of a conductive structure than along another region, and methods of forming integrated assemblies
Some embodiments include an integrated assembly having a conductive structure which includes a semiconductor material over a metal-containing material. A stack of alternating conductive levels and insulative levels is over the conductive structure. A partition extends through the stack. The partition has wall regions, and has corner regions where two or more wall regions meet. The conductive structure includes a first portion which extends directly under the corner regions, and includes a second portion which is directly under the wall regions and is not directly under the corner regions. The first portion has a first thickness of the semiconductor material and the second portion has a second thickness of the semiconductor material. The first thickness is greater than the second thickness. Some embodiments include methods of forming integrated assemblies.
1. A method of forming an integrated assembly, comprising:
forming a construction comprising a conductive structure, and comprising a stack of alternating first and second levels over the conductive structure; the conductive structure comprising a semiconductor material over a metal-containing material; the conductive structure comprising a first portion and a second portion; the first portion comprising a thicker region of the semiconductor material than the second portion; the first levels comprising a first composition and the second levels comprising a second composition; the second composition being different than the first composition;
forming slits extending through the stack to the conductive structure; the slits joining to one another at intersect regions; the intersect regions being over the first portion of the conductive structure and not over the second portion of the conductive structure;
after forming the slits, replacing the first composition with conductive material; and
forming insulative material within the slits.
2. The method of claim 1 wherein the first composition comprises silicon nitride, and wherein the second composition comprises silicon dioxide.
3. The method of claim 1 wherein the conductive material is conductive wordline material of a NAND assembly; wherein the insulative material within the slits forms a partition; and wherein the partition divides the NAND assembly into sub-blocks.
4. The method of claim 3 wherein the conductive structure is a source structure coupled with the NAND assembly.
5. The method of claim 1 wherein the first portion of the conductive structure only comprises the semiconductor material.
6. The method of claim 1 wherein the semiconductor material comprises conductively-doped silicon.
7. The method of claim 1 wherein the formation of the slits forms cavities extending into the first portion under the intersect regions.
8. The method of claim 7 wherein at least one of the cavities is deeper than the second thickness.
9. The method of claim 1 wherein the conductive structure has an overall thickness; wherein the semiconductor material of the first portion comprises greater than about half of said overall thickness; and wherein the semiconductor material of the second portion comprises less than or equal to about half of said overall thickness.