CHARACTERIZATION OF A LOW-TEMPERATURE, LOW-PRESSURE PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION TETRAETHYLORTHOSILICATE OXIDE DEPOSITION PROCESS

A low temperature (180 degrees C) and pressure (less than or equal to 750 mTorr) tetraethylorthosilicate (TEOS) oxide deposition process was developed and characterized in a commercially available plasma enhanc ed chemical vapor deposition reactor. The reactor uses a dual frequenc y, capacitively coupled, parallel plate electrode design, which employ s multistation sequential deposition to enhance throughput and uniform ity. Deposition rate, within wafer film thickness uniformity, and film stress were characterized as a function of process pressure, gas comp osition, rf power, and temperature. Production quality oxide films wer e deposited using low TEOS flow rate (45 seem), high oxygen flow rate (4000 sccm), and low pressure (500 mTorr). Deposition rate increased l inearly with TEOS flow rate and decreases with oxygen flow rate. Depos ition rate was weakly dependent on high frequency power and independen t of pressure in this low pressure regime. Film thickness uniformity a cross a 200 mm wafer improved with decreasing TEOS flow rate and press ure. Uniformity was a weak function of oxygen flow rate and high frequ ency power. Film stress became more compressive with decreasing TEOS f low rate and was a weak function of oxygen flow rate, high and low fre quency power, and pressure. A high quality TEOS oxide was deposited in this new processing regime, suitable for integrated circuit applicati ons. (C) 1997 American Vacuum Society.