Some embodiments include a method of forming an assembly (e.g., a memory array). A first opening is formed through a stack of alternating first and second levels. The first levels contain silicon nitride, and the second levels contain silicon dioxide. Some of the silicon dioxide of the second levels is replaced with memory cell structures. The memory cell structures include charge-storage regions adjacent charge-blocking regions. Tunneling material is formed within the first opening, and channel material is formed adjacent the tunneling material. A second opening is formed through the stack. The second opening extends through remaining portions of the silicon dioxide, and through the silicon nitride. The remaining portions of the silicon dioxide are removed to form cavities. Conductive regions are formed within the cavities. The silicon nitride is removed to form voids between the conductive regions. Some embodiments include memory arrays.
1. An assembly, comprising:
a channel to conduct current; the channel including a first channel portion and a second channel portion under the first channel portion;
a first memory cell structure located between a first gate and the first channel portion; the first memory cell structure including a first charge-storage region and a first charge-blocking region; the first charge-blocking region being located between the first charge-storage region and the first gate; the first charge-blocking region comprising silicon oxynitride and the first charge-storage region comprising silicon nitride;
a second memory cell structure under the first memory cell structure and located between a second gate and the second channel portion; the second memory cell structure including a second charge-storage region and a second charge-blocking region; the second charge-blocking region being located between the second charge-storage region and the second gate; the second charge-blocking region comprising silicon oxynitride and the second charge-storage region comprising silicon nitride;
a void located between the first and second gates, and between the first and second memory cell structures;
the first gate comprising conductive material over the void and spaced from the void by low-density silicon dioxide;
the second gate comprising conductive material under the void and spaced from the void by low-density silicon dioxide;
a first liner between the silicon nitride of the first charge-storage region and the void;
a second liner between the silicon nitride of the second charge-storage region and the void;
a first dielectric barrier region being between the first gate and the first charge-blocking region;
a second dielectric barrier region being between the second gate and the second charge-blocking region; and
wherein the first and second dielectric barrier regions comprise high-k material;
wherein an edge of the high-k dielectric material of the first dielectric barrier region is directly against the void; and wherein an edge of the high-k dielectric material of the second dielectric barrier region is directly against the void.
2. The assembly of claim 1 wherein the first and second liners comprise silicon oxynitride.
3. The assembly of claim 1 wherein the first charge-blocking region comprises silicon dioxide between the silicon oxynitride of the first charge-blocking region and the silicon nitride of the first charge-storage region; and wherein the second charge-blocking region comprises silicon dioxide between the silicon oxynitride of the second charge-blocking region and the silicon nitride of the second charge-storage region.