Vertical memory cell with mechanical structural reinforcement

A reinforced vertical-NAND structure, comprising:

• a first set of interleaved lined oxide and metallic layers formed into first and second vertical structures,
• the first vertical structure rising from a first section of a substrate and the second vertical structure rising from a second section of the substrate;
• a reinforcing layer comprising sheets, which are distinct and laid across unlined upper oxide surfaces of respective tops of the first and second vertical structures;
• and
• a second set of interleaved lined oxide and metallic layers formed into third and fourth vertical structures,
• the third vertical structure rising from the sheet corresponding to the first vertical structure and the fourth vertical structure rising from the sheet corresponding to the second vertical structure.

A method of assembling a reinforced-NAND structure, the method comprising:

• forming a first set of interleaved oxide and nitride layers formed into first and second vertical structures rising from first and second sections of a substrate, respectively;
• forming a reinforcing layer comprising sheets, which are distinct and laid across respective tops of the first and second vertical structures, and bridges connecting the sheets;
• and
• forming a second set of interleaved oxide and nitride layers into third and fourth vertical structures rising from the sheets corresponding to the first and second vertical structures, respectively.

A method of assembling a reinforced-NAND structure, the method comprising:

• building, on first and second sections of a substrate, a structure comprising a reinforcing layer interposed between first and second sets of interleaved oxide and nitride layers;
• etching portions of the second set of interleaved oxide and nitride layers between the first and second sections of the substrate;
• etching the reinforcing layer to form distinct sheets and bridges between the distinct sheets;
• and
• etching portions of the first set of interleaved oxide and nitride layers between the first and second sections of the substrate.

A method of assembling a reinforced-NAND structure, the method comprising:

• alternately depositing oxide and nitride on a substrate to form interleaved oxide and nitride layers;
• depositing reinforcing layer material on an uppermost oxide layer to form a reinforcing layer;
• alternately depositing oxide and nitride on the reinforcing layer to form interleaved oxide and nitride layers;
• forming poly-silicon lined oxide posts through the oxide, nitride and reinforcing layers;
• etching portions of the oxide and nitride layers above the reinforcing layer down to the reinforcing layer;
• etching exposed portions of the reinforcing layer into bridges;
• and
• etching portions of the oxide and nitride layers below the reinforcing layer down to the substrate.