LPCVD Simulation

Safety Procedures

Please be aware of any potential hazards prior to operating any experiments. There are no chemicals used in this computational experiment. You're using a computer so you should observe all the usual precautions regarding ergonomics: sit up straight, keep your feet flat, and keep the monitor at eye level. Emptying the cache and occasionally talking to the computer, perhaps about its weekend plans, are good ways to keep it running at optimal speed.

Objectives

1. Review Dr. Yang's introduction to COMSOL in the video below. He'll introduce you to COMSOL, the LPCVD reactor, and he'll solve the example from the previous pre-lab questions. You'll be able to see the similarities pretty quickly and by the time you're done with the video you should be able to solve this year's pre-lab question if you want to.

2. Make sure the entire team can run the 3-zone boat reactor simulation in COMSOL and analyze the Si layer properties using MATLAB.

3. Complete a 2ᵏ factorial design (also called "design of experiment") to determine which operating parameters have the largest effect on Si layer properties.

Tips

1. Attached at the bottom of this page are 

   1. Dr. Yang's slides from the video above (Dr Yang Introduction to COMSOL)

   2. The COMSOL model file for a simple boat reactor (boat_reactor.mph, referred to as "boat reactor LPCVD.mph" in Dr. Yang's video - file to be updated Sp22)

   3. The COMSOL model file for a 3-zone boat reactor (file to be updated Sp22)

   4. A MATLAB live script to analyze the Si layer properties (file to be updated Sp22)

   5. A sample data file for use with the MATLAB live script (sampleData)

   6. An introduction to the 2ᵏ factorial design process mentioned above. (Agilent DoE Introduction)

2. The Pareto chart will almost always reveal temperature as the dominant factor, often to the point of obscuring all other factors. In this case you can leave temperature off the Pareto chart and discuss its role elsewhere.

3. In your report you should reference COMSOL website once.

4. Your Theory section should include 

   1. A figure indicating the geometry used in the simulation which clearly indicates which physics occur in which zones.

   2. The governing equations for each of the physics used in your simulation (you can find these by clicking on the various physics packages under the "Component" section of your model).

References

1. Fogler, H.S., Essentials of Chemical Reaction Engineering; Pearson Education: Boston, 2011.

2. Jensen, K.F. Micro-reaction engineering applications of reaction-engineering to processing of electron and photonic materials. Chem. Eng. Sci. 1987, 42, 923-958.

3. Kleijn, C.R.; van der Meer, T.H.; Hoogendoorn, C.J., A mathematical model for LPCVD in a single wafer reactor. J. Electrochem. Soc. 1989, 136, 3423-3433.

4. Komiyama, H.; Shimogaki, Y,; Egashira, Y., Chemical reaction engineering in the design of CVD reactors. Chem. Eng. Sci. 1999, 54, 1941-1957.

5. Roenigk, K.F.; Jensen, K.F., Analysis of multicomponent LPCVD processes: Deposition of pure and in situ doped poly-Si. Electrochem. Soc.: Solid State Sci. Tech. 1985, 132, 448-454.

6. Zambov, L.M., Optimum design of LPCVD reactors. J. Phys. IV 1995, 5, 269-276.

7. Sachs, E.; Prueger, G.H.; Guerrieri, R., An equipment model for polysilicon LPCVD. IEEE Trans. Semiconduct. Manufactur. 1992, 5, 3-13.

8. Voutsas, A.T.; Hatalis, M.K., Structure of as-deposited LPCVD silicon films at low deposition temperatures and pressures. J. Electrochem. Soc. 1992, 139, 2659-2665.

9. Setalvad, T.; Tachtenberg, I.; Bequette, B.W.; Edgar, T.F., Optimization of a low-pressure chemical vapor deposition reactor for the deposition of thin films. Ind. Eng. Chem. Res. 1989, 28, 1162-1170.

Agilent DoE Introduction (PDF file)

Dr Yang Introduction to COMSOL (PDF file)

Sample Data (TXT file)

COMSOL Model Files (MPH file) 

MATLAB Live Script (MLX file)