Semiconductor device and method for fabricating the same using damascene process

A method for fabricating a semiconductor device using a damascene process, comprising the steps of.

• forming a dummy gate on a semiconductor substrate, the dummy gate including a dummy gate insulating film and a dummy gate electrode;
• forming an oxide film over the semiconductor substrate using an LDD oxidation process;
• forming an Al2O3 film over the semiconductor substrate and the dummy gate;
• heat-treating the semiconductor substrate;
• forming source and drain regions in the semiconductor substrate;
• activating the source and drain regions;
• forming an interlayer insulating film over the substrate;
• polishing and planarizing the interlayer insulating film and the Al2O3 film using a Chemical Mechanical Polishing process to expose the dummy gate electrode;
• etching the dummy gate electrode and the dummy gate insulating film in sequence to form a groove defining a gate electrode region;
• forming a gate insulating film on a surface of the groove;
• and
• forming a doped polysilicon film or a gate metal film on the gate insulating film in the groove.

A method of fabricating a semiconductor device using a damascene process, comprising the steps of:

• forming a dummy gate on a semiconductor substrate, the dummy gate including a dummy gate insulating film and a dummy gate electrode;
• wet-etching the dummy gate;
• forming an AlON film over the semiconductor substrate;
• heat-treating the semiconductor substrate to transform the AlON film into an Al2O3 film;
• heat-treating the semiconductor substrate on which the Al2O3 film was formed;
• implanting low concentration impurity ions into the semiconductor substrate to form an LDD region in the substrate;
• forming spacers on sidewalls of the dummy gate;
• implanting high concentration impurity ions into the substrate to form a source/drain region;
• heat-treating the substrate to activate the implanted high concentration impurity ions;
• forming an interlayer insulating film on the semiconductor substrate;
• polishing and planarizing the interlayer insulating film and the Al2O3 film using a Chemical Mechanical Polishing process to expose the dummy gate electrode;
• etching the dummy gate electrode and the dummy gate insulating film in sequence to form a groove defining a gate electrode region;
• forming a gate insulating film on a surface of the groove;
• and
• forming a doped polysilicon film or a gate metal film on the gate insulating film in the groove, thereby forming a gate of the semiconductor device.

A semiconductor fabrication method, comprising the steps of:

• forming a film over a dummy gate structure, which is disposed over a semiconductor substrate, the film having an etch selectivity that is different than an etch selectivity of the dummy gate structure;
• removing a portion of the film to expose the dummy gate structure;
• selectively etching the dummy gate structure to form a groove defined by a portion of the film and the semiconductor substrate;
• depositing an insulating film within the groove;
• and
• forming a gate material over the insulating film in the groove.

A semiconductor device, comprising:

• a substrate;
• an insulating film and a gate material formed over the substrate, the insulating film having a base section narrower than an upper section thereof;
• and
• a film formed along sides of the insulating film.

A semiconductor fabrication method, comprising the steps of:

• forming a dummy gate structure on a semiconductor substrate, the dummy gate structure having a base section narrower than an upper section thereof;
• forming a film over the dummy gate structure;
• removing a portion of the film and the dummy gate structure to form a groove defined by portions of the film and the semiconductor substrate;
• depositing an insulating film within the groove;
• and
• forming a gate material over the insulating film in the groove.