Semiconductor devices including stack oxide materials having different densities or different oxide portions, and semiconductor devices including stack dielectric materials having different portions

A semiconductor device, comprising:

• a stack of alternating oxide materials and conductive materials, one or more of the oxide materials of the stack comprising at least two different oxide portions directly vertically adjacent to one another;
• charge storage structures laterally adjacent to the conductive materials of the stack, the charge storage structures comprising a uniform height across a length thereof and no portion of the conductive materials of the stack overlying or underlying the charge storage structures;
• a charge block material between the charge storage structures and the respective laterally adjacent conductive materials of the stack, portions of the charge block material extending beyond upper boundaries and lower boundaries of the conductive materials of the stack along an entirety of the length of the charge storage structures;
• and
• a channel material extending through the stack of alternating oxide materials and conductive materials.

A semiconductor device, comprising:

• a stack of alternating dielectric materials and conductive materials, the dielectric materials of the stack comprising at least two different portions abutting one another along horizontal interfaces therebetween;
• charge storage structures laterally adjacent to the conductive materials of the stack, the charge storage structures comprising a uniform height across a length thereof and the height of the charge storage structures the same as the height of the laterally adjacent conductive materials of the stack;
• a charge block material between the charge storage structures and the respective laterally adjacent conductive materials of the stack, a portion of the charge block material extending within recessed regions of the dielectric materials of the stack;
• and
• a channel material vertically extending through the stack of alternating dielectric materials and conductive materials, sidewalls of the channel material exhibiting a slope.