Rapid thermal processing (RTP) has emerged as a dey manufacturing technique for semiconductor device fabrication. In comparison to conventional furnace processing, where large batches of wafers are loaded into tube furnaces, RTP presents advantages in temperature control, ambient purity, cycle time and process flexibility. The fundamental flexibility of RTP in creating new types of thermal processes arises from the dynamic control of the heat source temperature, which permits fast heating combined with dynamic optimization of temperature uniformity. This paper illustrates the evolution of RTP system design to include concepts such as wafer rotation, axisymmetric heater design and multiple point dynamic temperature control. The resulting improvements in temperature uniformity and repeatability are demonstrated using process results which show that the new generation ofRTP equipment can control the temperature distribution on both 200 and 300 mm wafers with a 3#sigma# (3 standard deviations) range below 3 deg C. The power requirements for fast heating processes where minimization of diffusion is essential, such as ion-implantation damage annealing, are analyzed, and it is shown that heating rates up to 280 deg C/s can be achieved on 300 mm wafers. RTP, as a uniquely agile manufacturing process, will greatly assist the introduction of the new materials and processes required to extend metal-oxide-semiconductor (MOS) techology to its natural limits over the next 20 years, and is also posed to make significant contributions in emerging technologies including nanoelectronics, microelectromechanical devices and nonsilicon applications, including the processing of magnetic materials. direct c 1999 Elsevier Science Ltd. All rights reserved.
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