Optimization of rapid thermal processing for uniform temperature distribution on wafer surface

Abstract

An optimization of rapid thermal processing (RTP) was conducted to obtain uniform temperature distribution on a wafer surface by using linear programming and radiative heat transfer modeling. The results show that two heating lamp zones are needed to maintain uniform wafer temperature and the optimal lamp positions are unique for a given geometry and not affected by wafer temperatures. The radii of heating lamps, which were obtained by optimization, are 45 mm and 108 mm. The emissivity and temperature of the chamber wall do not significantly affect the optimal condition. With obtained optimum geometry of the RTP chamber and lamp positions, the wafer surface temperatures were calculated. The uniformity allowance of the wafer surface is less than ±1℃ when the mean temperature of the wafer surface is 1000℃.

Sparse identification modeling and predictive control of wafer temperature in an atomic layer etching reactor

“…To manifest the superior performance of radiative heating, the geometrical design of the reactor is crucial. Various geometric configurations of lamp groups have been explored in prior works: a parallel configuration of individual lamps positioned directly above the wafer (Gyurcsik and Sorrell, 1991), a ring structure with varying radii above the wafer (Oh et al, 2009), and a structure where there are lamps both above the wafer and on the side of the wafer (Theodoropoulou et al, 1998). Baker and Christofides (1999) also proposed a complete configuration with circular lamps positioned above, on the side, and beneath the wafer in a quartz process chamber.…”

“…Nevertheless, prior studies have been primarily concentrated on optimizing the power supplied to the lamps to achieve a uniform temperature profile in a steady-state condition after thousands of seconds, which is similar to an open-loop control strategy (Gyurcsik and Sorrell, 1991;Cho et al, 1994;Theodoropoulou et al, 1998;Oh et al, 2009). There is limited work focused on transient temperature analysis and real-time control.…”

Numerical evaluation on surface temperature uniformity of multi-zone and single-zone ceramic heaters with the electrostatic chuck

“…Uniformly heating a chuck is essential to construct uniform critical dimensions on the wafer. The etching, deposition rate, physical, electrical, optical properties, and the composition ratio of the deposited material are closely related to the temperature [1][2][3][4]. A small variation of the local temperature causes a large deviation of deposition and etching rates along the wafer.…”