Observation of silicon wafer emissivity in rapid thermal processing chambers for pyrometric temperature monitoring

Abstract

The emissivity of silicon wafers in a rapid thermal processing chamber has been measured as a function of the wafer temperature. Wafers with different surface roughness and layers have been studied. For transparent wafers, both sides of the wafer affect the emissivity. This emissivity is not only affected by surface roughness, but also by the layers deposited on the wafer. It has also been observed that while the emissivity increases rapidly as the temperature increases from its room value to 600 °C, the emissivity decreases with a slope of −8.89×10−5 °C−1 for temperatures larger than 600 °C.

Natural Convection Heat Transfer Around Microfin Arrays

“…Since the cover chamber is large enough to neglect directional variation of irradiation from the surroundings, the flat plate is regarded as a diffuse-gray surface in a large enclosure. The radiation heat transfer rate is estimated as follows: The emissivity, ", of the silicon wafer is found from Nulman et al [20] and Ravindra et al [21]. They measured the emissivity of the pure silicon surface and the SiO 2 surface on a silicon substrate.…”

“…The heat loss through the thin foil-type thermocouple is also estimated by the simplified one-dimensional conduction analysis, even though it turns out to be as small as about 1-2%. The main uncertainty for estimating the amount of radiation heat transfer, comes from emissivity values [20,21]. Uncertainties are evaluated based on the method proposed by Coleman and Steele, Jr. [22].…”

Numerical investigation on optical and heat transfer characteristics of a rapid thermal annealing system for LCD manufacturing

“…For conduction and radiation heat transfer analysis, an implicit finite-difference method is used to integrate transient and spatial terms in Eqs. (7), (8), and (10). The Neumann boundary conditions are imposed at z = 0 and z = d 1 + d 2 + d 3 in the thermal analysis.…”

“…In the thermal analysis, the finite difference method is used to solve the integro-differential type of Eqs. (7), (8), and (10). When the transmitting layer is so thin that its thickness is comparable to the radiation wavelength, there can be interference between incident and reflected waves.…”

“…The surface emissivity is obviously a critical parameter in the temperature control and thermal modeling of the RTA processing of semiconductors. The temperature-dependent emissivity of silicon has been studied by using different heating meth- ods, including furnace [8,9], electron beam [10], and contact heating [9]. Chen and Borca-Tasciuc [11] investigated the photon effect on radiative properties of silicon during rapid thermal processing.…”