LPCVD vertical furnace optimization for undoped polysilicon film deposition

Development of an original model for the synthesis of silicon nanodots by Low Pressure Chemical Vapor Deposition

“…Numerous authors have developed numerical models of CVD reactors linking the elaboration conditions to the deposition rate of each of the species [18,[21][22][23]. To our knowledge, all these works concern conventional silicon layers of thicknesses at least equal to several tens of nanometers.…”

Computationally efficient modeling of wafer temperatures in a low-pressure chemical vapor deposition furnace

“…Although many researchers presented theoretical and experimental evidence for wafer radial temperature variations [3], [17], [18], the variations are expected to be small for all the wafers except the end wafers and thus have been neglected by many researchers [6], [9], [12], [14], [19]. In our case, since the wafer-to-wafer temperature uniformity is the only interesting aspect, this assumption will reduce the degree of complexity significantly without adding severe restriction to the model.…”

“…Equation (16) is rewritten as (18) for . Considering (17) and (18) Equations (17) and (18) can be written as (19) and (20) Rearrange (20) to solve for (21) Substituting (21) into (19) and rearranging the equation, we have (22) where and are by and by identity matrices. Denoting we solve (22) to obtain (23)…”

Multiscale simulation of silicon film growth

“…Two points are very important to obtain reliable macroscale simulations: the adopted parameters (rates of chemical reactions involved, thermodynamic and transport features of the gaseous mixture) and the detailed description of the reactor geometry. An example of these outcomes is summarized in figure 1 where some overall results inherent the polysilicon deposition from silane and hydrogen mixtures in a vertical hot wall reactor (ASM type) are presented [6]. It is important to note that by means of a standard LPCVD model (i.e., annular + intrawafer zones), by several reactor simulations, it is possible to derive efficiency maps that explore the process features and thus help in the process definition.…”

“…However, for particular reactor configurations, these equations can be reduced to the combination of 1D models whose solution is computationally less expensive than the previous ones [5]. By the way, the simulation of LPCVD reactors is indeed a process where the second approach can be safely adopted [2,6]. For our purposes, the main outcome of the simulation are the growth rate profile on the wafer and the gas temperature profile within the reactor.…”