Optoelectronic synaptic device including quantum dot(qd)-transition metal chalcogenide(tmd) heterojunction

A method of manufacturing an optoelectronic synaptic device, the method comprising:

• combining a two-dimensional semiconductor material on a silicon oxide substrate;
• forming a two-dimensional semiconductor material layer by wet-transferring the two-dimensional semiconductor material on another semiconductor substrate;
• forming an electrode layer by depositing a plurality of metal layers arranged to be spaced apart from each other on a portion of the two-dimensional semiconductor material layer;
• and
• forming a photoactive layer by applying an inorganic quantum dot colloidal solution and a ligand solution to some other surfaces on the two-dimensional semiconductor material layer and coating and drying the solutions,
• wherein a heterojunction is formed by directly contacting the inorganic quantum dots and the two-dimensional semiconductor material layer each other, and
• wherein the ligand solution is a mixed solution in which an organic ligand and an organic solvent are mixed, and the organic ligand solution has a short carbon chain or ring of C1 to C8,and includes any one or more functional groups selected from a thiol group, an amine group, a carboxyl group, and a combination thereof, and
• wherein at least a portion of a surface of the inorganic quantum dots, except an area where the heterojunction is formed together with the two-dimensional semiconductor material, is covered with the organic ligand.