Microelectronic devices with tunneling structures having an oxide region extending above a high-k material region

A microelectronic device, comprising

• a stack structure comprising vertically repeated tier groups, the tier groups individually comprising at least one conductive structure and at least one insulative structure;
• and
• at least one vertical structure extending substantially vertically through the stack structure, the at least one vertical structure individually comprising:
• a channel structure comprising:
• an upper channel structure;
• and
• a lower channel structure below the upper channel structure;
• a tunneling structure horizontally around the lower channel structure, the tunneling structure comprising a high-κ region between oxide sub-regions;
• an oxide region horizontally around the upper channel structure;
• and
• an oxide material of at least one of the oxide sub-regions continuing along the upper channel structure to define the oxide region.

A microelectronic device, comprising:

• a tiered stack comprising conductive structures and insulative structures arranged in vertically repeated tier groups;
• and
• at least one vertical structure extending substantially vertically through the tiered stack, the at least one vertical structure individually comprising:
• a channel structure;
• a continuous region of an oxide material horizontally around the channel structure;
• and
• a region of a high-κ material horizontally around a lower portion of the continuous region of the oxide material, the continuous region of the oxide material continuing above the region of the high-κ material.