Cyclic deposition method for thin film formation, semiconductor manufacturing method, and semiconductor device

A cyclic deposition method for thin film formation, comprising:

• forming a silicon thin film on an object by injecting a silicon precursor into a chamber in which the object is loaded, depositing silicon on the object, and performing a first purge, removing an unreacted portion of the silicon precursor and reaction by-products from the interior of the chamber;
• after forming the silicon thin film, pre-processing a surface of the silicon thin film by forming a plasma atmosphere in the chamber and supplying a first reaction source having a hydrogen atom;
• and
• after pre-processing the surface of the silicon thin film, forming the silicon thin film as an insulating film including silicon, by forming the plasma atmosphere in the chamber and supplying a second reaction source having one or more oxygen atoms, one or more nitrogen atoms, or a mixture thereof,
• wherein the insulating film has a wet etch rate of 0.4 to 0.6.