Method of manufacturing semiconductor device

A method of forming a semiconductor device, comprising:

• forming an interlayer insulating layer on an active pattern of a substrate;
• forming a gate trench in the interlayer insulating layer, the gate trench exposing a region of the active pattern;
• sequentially forming an interfacial layer and a high-k dielectric layer on the region of the active pattern that is exposed by the gate trench;
• and
• performing a first heat treatment at a pressure of from 1 Torr to 40 Torr and at a temperature of from 400° C. to 900° C.

A method of manufacturing of a semiconductor device comprising:

• forming an interlayer insulating layer on an active pattern of a substrate;
• forming a gate trench in the interlayer insulating layer, the gate trench exposing a region of the active pattern;
• forming a gate dielectric layer on the region of the active pattern exposed by the gate trench;
• transferring the substrate to a load lock chamber that is under a vacuum;
• transferring the substrate from the load lock chamber to a process chamber that is under a vacuum and performing a first heat treatment on the substrate in the process chamber;
• and
• forming a gate electrode in the gate trench on the gate dielectric layer,
• wherein a pressure within the process chamber is controlled at a pressure of from 1 Torr to 40 Torr for performing the first heat treatment.