PLASMA PROCESS CONTROL USONG MULTIPLE OPTICAL SENSORS

THE DEVELOPMENBT OF REAL-TIME PROCESS CONTROL FOR SEMICONDUCTOR DEVICE FABRICATION IS CRITICAL TO ADVANCING THE TECHNOLOGY IN MANUFACTURING MICROELECTRONIC CIRCUITS. IN PHASE I, RECENT ADVANCES IN TUNABLE DIODE LASER FABRICATION AND DETECTION TECHNOLOGY WILL BE EXPLOITED TO DEVELOP COMPACT AND COST EFFECTIVE INSTRUMENTATION FOR PLASMA PROCESS MONITORING AND CONTROL. PHASE I WILL FOCUS ON FLUORO-CARBON-BASED PLASMAS SUCH AS THOSE USED IN THE ETCHING OF SILICON, OXIDES, CERTAIN METALS, AND SILICIDES. IN SITU MEASUREMENTS WILL BE PERFORMED IN A REFERENCE CELL PLASMA RECTOR WHICH IS INSTRUMENTED WITH ACCD CAMERA SYSTEM FOR OPTICAL EMISSION SPECTROSCOPY. THE PROTOYPE DIODE LASER SENSOR WILL BE USED TO COMPLEMENT THE EMISSION MEASUREMENTS IN MEASURING ADDITIONAL PLASMA PROPERTIES, INCLUDING THE CONCENTRATIONS OF NEUTRAL RADICALS, FEED GAS DISSOCIATION FRACTIONS, AND THE CONCENTRATIONS OF GAS PHASE ETCH PRODUCT SPECIES. A CHEMOMETRIC-BASED APPROACH WILL BE USED TO DEFINE CORRELATIONS BETWEEN PARAMETERS MEASURED WITH THE LASER AND EMISSION SENSORS AND MACROSCOPIC RESULTS OF THE PLASMA ETCH PROCESS. THE RESULTS OF PHASE I WILL PROVIDE AS BASIS FOR DETAILED EXPERIMENTAL EVALUATIONS OF PLASMA PROCESS CONTROL SCHEMES USING DIODE LASER INSTRUMENTATION COMBINED WITH OPTICAL EMISSION SPECTROSCOPY IN PHASE II. ANTICIPATED BENEFITS/POTENTIAL COMMERCIAL APPLICATIONS - THE PROPOSED INSTRUMENTATION HAS VERY STRONG POTENTIAL FOR COMMERCIAL APPLICATIONS IN MONITORING OR CONTROL OF MICROELECTONIC DEVICE FABRICATION PROCESSES. THE TECHNIQUES AND INSTRUMENTATION COULD POTENTIALLY BE APPLIED TO A WIDE VARIETY OF PLASMA PROCESSES, INCLUDING EITHERETCHING OR DEPOSITION PROCESSES, AND A WIDE RANGE OF MATERIALS, INCLUDING SEMICONDUCTORS, INSULATORS, METALS, ETC.