Twin channel access device for vertical three-dimensional memory

A memory device, comprising:

• a horizontally oriented access device having a vertically stacked structure, comprising:
• first horizontal gate portion;
• first horizontal channel horizontally separating a first source/drain region and a second source/drain region, and separated from the first horizontal gate by a dielectric material;
• a second horizontal gate portion separated from the first horizontal channel by the dielectric material;
• a second horizontal channel horizontally separating a third source/drain region and a fourth source/drain region, and separated from the second horizontal gate by the dielectric material;
• and
• a third horizontal gate portion separated from the second horizontal channel by the dielectric;
• a first horizontally oriented storage node coupled to the second source/drain region;
• and
• a second horizontally oriented storage node coupled to the fourth source/drain region.

A method of forming multi-tier, vertical three-dimensional (3D) memory, comprising:

• forming a horizontally oriented access device, in a first horizontal tier of the multi-tier, vertical 3D memory, the access device having a vertically stacked;
• first horizontal gate;
• first horizontal channel horizontally separating a first source/drain region and a second source/drain region, and separated from the first horizontal gate by a first gate dielectric;
• a second horizontal gate separated from the first horizontal channel by a second gate dielectric;
• a second horizontal channel horizontally separating a third source/drain region and a fourth source/drain region, and separated from the second horizontal gate by a third gate dielectric;
• and
• a third horizontal gate separated from the second horizontal channel by a fourth gate dielectric;
• forming a first horizontally oriented storage node coupled to the second source/drain region of the first horizontal channel;
• and
• forming a second horizontally oriented storage node coupled to the fourth source/drain region of the second horizontal channel.