Three-Dimensional Memory Device and Method

A device comprising:

• a bit line extending in a first direction, the bit line having a first T-shaped cross-section in a top-down view;
• a source line extending in the first direction, the source line having a second T-shaped cross-section in the top-down view;
• an isolation region between the source line and the bit line;
• a word line extending in a second direction, the second direction perpendicular to the first direction;
• a back gate isolator between the word line and each of the isolation region, a first portion of the bit line, and a second portion of the source line;
• a channel layer between the back gate isolator and the word line;
• and
• a data storage layer between the channel layer and the word line.

A method comprising:

• forming a word line between a pair of first dielectric layers;
• depositing a data storage layer on sidewalls of the first dielectric layers and a sidewall of the word line;
• depositing a channel layer on a sidewall of the data storage layer;
• depositing a first dielectric layer on a sidewall of the channel layer;
• forming a first isolation region on a sidewall of the first dielectric layer;
• removing a first portion of the first isolation region, a second portion of the first isolation region remaining after the removing;
• after removing the first portion of the first isolation region, patterning the first dielectric layer to form a back gate isolator;
• and
• forming a bit line and a source line at opposing sides of the second portion of the first isolation region, the back gate isolator separating the channel layer from a first portion of the bit line and a second portion of the source line.