Influence of gas composition on wafer temperature in a tungsten chemical vapor deposition reactor: Experimental measurements, model development, and parameter identification

Abstract

Experimental measurements of wafer temperature in a single-wafer, lamp-heated chemical vapor deposition system were used to study the wafer temperature response to gas composition. A physically based simulation procedure for the process gas and wafer temperature was developed in which a subset of parameter values were estimated using a nonlinear, iterative parameter identification method, producing a validated model with true predictive capabilities. With process heating lamp power held constant, wafer temperature variations of up to 160 K were observed by varying the feed gas H2/N2 ratio. Heat transfer between the wafer and susceptor was studied by shifting the instrumented wafer off the susceptor axis, exposing a portion of the wafer backside to the chamber floor. Model predictions and experimental observations both demonstrated that the gas velocity field had little influence on the observed wafer and predicted gas temperatures.

Simulation‐based design and experimental evaluation of a spatially controllable CVD reactor

“…That a good fit is obtained for the rate exponent of n = 0.5 (recommended by Joshi et al,1992) is significant because an accurate rate description for rates linear in WF 6 concentration and that pass through ds w / dt = 0 for x = 0 could not be found for these data. The different values of K k determined for each segment can be attributed to the different wafer surface temperatures in each segment as a result of gas composition differences (Chang et al,2001) or film surface condition differences resulting from the H 2 /Ar composition differences.…”

Real-time growth rate metrology for a tungsten chemical vapor deposition process by acoustic sensing

“…The reported process temperatures in this article are the estimated wafer temperatures, as determined by an instrumented wafer. 22 Prior to deposition, the wafers were cleaned in a 10% aqueous HF solution for 20 min, rinsed in deionized water, and blown dry with nitrogen. Cleaned wafers were loaded into the CVD reactor through a high vacuum load lock.…”

Thermal transportation simulation of a susceptor structure with ring groove for the vertical MOCVD reactor

“…As the gas velocity field has little influence on the wafer temperature [10], and the effect of natural convection on the temperature variation in the wafer is small [11], the gas velocity and natural convection are neglected. Thus, a coupled conductionradiation boundary condition is applied on the outer surfaces of the susceptor…”