US 12,444,606 B2
Methods for forming vertically layered ionic liquid crystal (ILC) structures on a semiconductor substrate
Dipak Aryal, Austin, TX (US); Antonio Luis Pacheco Rotondaro, Austin, TX (US); Takeo Nakano, Nirasaki (JP); Mitsuaki Iwashita, Nirasaki (JP); Ryuichi Asako, Nirasaki (JP); Tamotsu Morimoto, Nirasaki (JP); and Paul Abel, Austin, TX (US)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Nov. 9, 2023, as Appl. No. 18/388,240.
Prior Publication US 2025/0157820 A1, May 15, 2025
Int. Cl. H01L 21/033 (2006.01); C09K 19/04 (2006.01)
CPC H01L 21/0337 (2013.01) [C09K 19/04 (2013.01); H01L 21/0332 (2013.01); H01L 21/0335 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method to form a pattern on a semiconductor substrate, the method comprising:
depositing an ionic liquid crystal (ILC) solution on a surface of the semiconductor substrate, the ILC solution comprising ionic liquid crystals (ILCs) having cation head groups, alkyl tail groups and anions;
exposing an upper surface of the ILC solution to a gas phase, non-polar solvent, which promotes self-assembly of the ILCs into a vertically layered structure on the surface of the semiconductor substate, the vertically layered structure having alternating layers of head group layers and tail group layers, with the anions segregated to the head group layers; and
utilizing the vertically layered structure to form the pattern on the semiconductor substrate.