Thin tensile layers in shallow trench isolation and method of making same

The method of forming an isolation trench comprising:

• forming a recess in a substrate, wherein the recess comprises a sidewall;
• forming a film upon the sidewall under conditions that cause the film to be under a tensile load, wherein forming a film upon the sidewall comprises:
• forming an underlying film on the sidewall;
• and
• forming a nitride film on the underlying film, wherein the nitride film is formed by a chemical vapor deposition of silicon nitride;
• and
• filling the recess with a material that imparts a compressive load upon the sidewall under conditions that oppose the tensile load.

A method of forming an isolation trench comprising:

• forming a recess in a substrate, wherein the recess comprises a sidewall;
• forming a film upon the sidewall under conditions that cause the film to be under a tensile load, wherein forming a film upon the sidewall comprises:
• forming an underlying film on the sidewall;
• and
• forming a deposited nitride film on the underlying film, wherein the deposited nitride film is formed by chemical vapor deposition of silicon nitride at a temperature range from about 30 C. to about 60 C., at a power from about 300 Watts to about 400 Watts, and with a silicon nitride source selected from stoichiometric silicon nitride and solid solution silicon nitride;
• and
• filling the recess with a material that imparts a compressive load upon the sidewall under conditions that oppose the tensile load.

A method of forming an isolation trench comprising:

• forming a recess in a substrate, wherein the recess comprises a sidewall;
• forming a film upon the sidewall under conditions that cause the film to be under a tensile load, wherein forming a film upon the sidewall comprises:
• forming a first nitride film on the sidewall;
• forming an oxide film on the first nitride film, and
• forming a second nitride film upon the oxide film, further comprising:
• isolating the nitride and oxide films within the recess by performing a chemical mechanical polishing etch-back;
• and
• filling the recess with a material that imparts a compressive load upon the sidewall under conditions that oppose the tensile load.

A method of forming an isolation trench comprising:

• forming a recess in a substrate, wherein the recess has a sidewall;
• performing a trench preclean within the recess;
• forming a silicon nitride film on the sidewall by annealing the recess under conditions selected from an N2O ambient, an NH3 ambient, and combinations thereof, a temperature in a range from about 900 C. to about 1,100 C., and for a time in a range from about 12 minutes to about 18 minutes;
• forming an oxide film in the recess by a thermal oxidation in a range from about 900 C. to about 1,000 C. and for a time in a range from about 2 minutes to about 15 minutes, wherein the oxide film has a thickness in a range from about 5 nm to about 20 nm;
• annealing the recess to form an oxynitride film on the oxide film and a silicon oxynitride film between the sidewall and the oxide film, under conditions of an N2O ambient, a temperature in a range from about 900 C. to about 1,100 C., and for a time in a range from about 12 minutes to about 18 minutes;
• and
• forming an inner film upon the oxynitride film in a thickness range from about 10 nm to about 50 nm, wherein the inner film imparts a tensile load on the sidewall.