LPCVD profile simulation using a re-emission model

Abstract

A new, physical based 3-D profile simulator has been developed that includes the dominant effect of re-emission. This simulator is part of the Stanford Profile Emulator for Etching and Deposition in ! C -Engineering (SPEEDIE). Unlike previous simulators which consider only the arrival of deposition precursors by unshadowed direct transport and by surface diffusion, SPEEDIE also considers transport into shadowed areas by adsorption and re-emission. The importance of re-emission was established by using overhang test structures to separate the roles of surface diffusion and re-emission For the depositions investigated (SiO,, poly-Si and W) it was found that re-emission dominates over surface diffusion in controlling surface contours. Using the simulator to fit experimental LPCVD SiO, profiles, it was found that a single constant sticking coefficient (SJ model with a cosine re-emission distribution gave excellent fits independent of geometry for a given deposition condition. Both Monte Carlo and analytic methods are used to calculate the precursor flux along the growing surface.

Simulation studies on PECVD SiO<inf>2</inf> process aiming at TSV application

“…As for the surface diffusion mechanism, we did not take it into consideration because its influence on the morphology of Si0 2 film deposition was tiny, which was confirmed due to many experiment results. [3] In this simulation, the sticking coefficient is the key parameter determining the step coverage characteristic.…”

“…Researchers at Stanford University had used a Monte Carlo simulation method (also called stochastic simulation method) to calculate the final angular distribution of ions. [3,4] The distribution function can be given as follows:…”

“…Up to now, a lot of studies have been conducted on this issue. A well-known model based on the device surface transportation is shown below: [1,2] REACT~'TS (3) gee) =f ield in the sheath. That is to say, the angle distribution of neutral particles is isotropic.…”

“…As for the surface diffusion mechanism, we did not take it into consideration because its influence on the morphology of Si0 2 film deposition was tiny, which was confirmed due to many experiment results. [3] In this simulation, the sticking coefficient is the key parameter determining the step coverage characteristic.As for ions in ion source, in which the thickness of sheath was well beyond the molecular mean free path, the collisions occurred in the sheath among the ions determined the angle distribution of ions. Researchers at Stanford University had used a Monte Carlo simulation method (also called stochastic simulation method) to calculate the final angular distribution of ions.…”

3D Simulation of Topography and Doping Processes at FhG

“…A reticle with programmed defects on it was printed on a g-line, 0.55 NA Canon stepper with a=O. 5. The resist was the TSMR V3 system of Tokyo Ohka, spun on a bare silicon substrate with final thickness of 1.5 micron.…”