Abstract:
Currently, metal oganic chemical vapor deposition
(MOCVD) is the most suitable technology for large-scale
preparation of thin-film materials, with the advantage of large
expitaxial area, good repeatability, precise componential
control, deposition rate, etc. It is a multi-disciplinary complex
system, and MOCVD process contains a large number of
complex physical and chemical processes with complicated
reaction mechanism and growth kinetics. The core part of
MOCVD system is reactor. In order to grow high-quality thinfilm
by MOCVD, the flow fields, thermal fields and chemical
reactions mechanism of MOCVD reactor must be studied in
depth. In this paper, MOCVD was 3D numerically simulated by
computational fluid dynamics software. The flow field, the
thermal field and the gas -phase pre-reaction that affect the
structure and properties of thin-films have been intensively
studied, and the experimental results and the simulation results
under same operating condition are compared to verify the
reliability of the simulation results. Achievements are as follows:
1.Use home-made MOCVD equipment to grow thin-films which
can be used to machine semiconductor LED chip on polished
silicon substrate and collect parameters in the process as
boundary conditions of numerical simulation. The N & K
versatile film tester is also used to measure the thickness of the
sample and to analysis the thickness distribution trends of thin
film on a substrate, preparing to verify the reliability of the
simulation results. 2. Establish the geometric model and grid
model of MOCVD reactor chamber, and import to computational
fluid dynamics software Fluent for numerical simulation, and
then compare the results of numerical simulation and
experimental results. It is found that the simulation deposition
rate distribution curve after fitting with an empirical formula
generally coincides with the experimental distribution curve. 3.
Analyze the distribution of temperature, velocity, mass fraction,
deposition rate and the pre-reaction conditions which seriously
affect the quality of films, and get to know the state of thermal
and flow fields in the reaction chamber and the conditions and
regions of pre-reactions. Due to the low gas velocity in the area
near the center of the substrate, it more greatly subjects to DEZn and O2 reaction and 'decomposition reaction of DEZn, which
also explains the film's thinner deposition on the inner
circumference of the substrate, namely, consumption of raw
materials being not promptly replenished.
Description:
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.
