Rapid thermal multiprocessing using multivariable control of circularly symmetric 3 zone lamp

A multiprocessing technology for overcoming the temperature nonuniformity limitations of rapid thermal processing is described. It is shown that the nonuniformity can be corrected by dynamic control of the spatial optical flux profile through two key innovations: (1) a lamp system in which tungsten-halogen point sources are configured in three concentric rings to provide a circularly symmetric flux profile, and (2) multivariable control whereby each of the three rings is independently and dynamically controlled to provide for control over the spatial flux profile. Good temperature uniformity over a wide range of temperatures, pressures, and gas flow rates, thereby adding process flexibility is demonstrated. Implant annealing, oxidation, and CVD of Si have been performed with excellent process uniformity. Multiprocessing has been demonstrated by in situ fabrication of an MOS capacitor.<>