Method for forming trench isolation regions

A method for forming trench isolation regions on a substrate, comprising:

• forming a trench in a surface of the substrate;
• forming a silicon nitride layer on the surface of the substrate, including the trench;
• uniformly distributing a gas over the surface of the silicon nitride layer, wherein the gas does not react to deposit a layer on the nitride layer;
• and
• while the gas is uniformly distributed over the surface of the silicon nitride layer, starting a reaction to deposit an insulation layer filling the trench over the silicon nitride layer.

A method for forming trench isolation regions on a substrate, comprising:

• forming a trench in a surface of the substrate;
• forming a nitride layer on the surface of the substrate, including the trench;
• in a chemical vapor deposition (CVD) apparatus, forming and maintaining a gas distribution region uniformly over the surface of the nitride layer;
• and
• while the gas distribution region is uniformly distributed over the surface of the nitride layer, simultaneously introducing ozone gas and Tetra Ethyl Ortho-Silicate (TEOS) into the CVD apparatus to deposit an insulation layer filling the trench.