Manufacturing method of esd protection device

Abstract

A manufacturing method of the ESD protection device includes the following steps. A surface treatment is performed on the substrate. A link layer is formed on the substrate after the surface treatment, wherein a material of the link layer includes a metal material. A progressive layer is formed on the link layer, wherein a material of the progressive layer includes a non-stoichiometric metal oxide material, and an oxygen concentration in the non-stoichiometric metal oxide material is increased gradually away from the substrate in a thickness direction of the progressive layer. A composite layer is formed on the progressive layer, wherein the composite layer includes a stoichiometric metal oxide material and a non-stoichiometric metal oxide material, and a ratio of the non-stoichiometric metal oxide material and the stoichiometric metal oxide material in the composite layer may make a sheet resistance value of the composite layer 1×107 to 1×108 Ω/sq.

Dependencies are inferred from the claim text.