Methods and devices for 3D NAND using silicon-and-halogen-containing materials

A semiconductor processing method comprising:

• forming a first layer of material in one or more recesses defined in alternating layers of material on a substrate in a processing region of a semiconductor processing chamber, wherein the first layer of material is a first silicon-containing material;
• subsequent to forming the first layer of material, forming a second layer of material on the first layer of material, wherein the second layer of material is a fluorine-doped silicon-containing material;
• and
• subsequent to forming the second layer of material, forming a third layer of material on the second layer of material, wherein the third layer of material is a second silicon-containing material;
• annealing the substrate subsequent to forming the first layer of material, the second layer of material, and the third layer of material;
• and
• subsequent to annealing the substrate, removing a portion of the first silicon-containing material, the the fluorine-doped silicon-containing material, and the second silicon-containing material.

A semiconductor structure comprising:

• a substrate having alternating layers of material formed on the substrate;
• and
• wherein one or more recesses are formed in the alternating layers of material;
• and
• a polycrystalline silicon material extending into the one or more recesses, wherein a second surface of polycrystalline material opposite a first surface of the polycrystalline silicon material overlies the alternating layers of material, wherein the polycrystalline silicon material is doped with a halogen, wherein the polycrystalline silicon material is characterized by a thickness of less than or equal to 30 nm, and wherein a portion of the polycrystalline silicon material disposed midway between the first surface and second surface has a higher halogen atomic concentration compared to the first surface and the second surface.