Full text
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| Author(s): |
Ronaldo Ruas
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2001-03-14 |
| Examining board members: |
Patrick Bernard Verdonck;
Ronaldo Domingues Mansano;
Stanislav Moshkalev
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| Advisor: | Patrick Bernard Verdonck |
| Abstract | |
In this work we study the influence of the electrode material on silicon plasma etching, using electrodes of aluminium, copper, tin and nickel. Through the technique of emission spectrocopy we see that the argon intensity for the different electrodes varies very much. We believe that this difference is caused by the fact that the secundary electron emission is dependent on the electrode material from one electrode to another. This dependence can cause changes in the density and energy of the electrons and will change the electron energy distibution function. In this way, the processes of excitation and ionization of argon will be different for each electrode material. The intensity of the argon spectrum using an electrode of aluminium was higher than for other electrodes. A compatible result was also obtained with the Langmuir Probe technique, where the average argon ion density was highest for the aluminium electrode. The etch rate of the silicon etching process in S\'F IND. 6\' also varied over a large range. The etch rate for the tin electrode was 12% higher than for aluminium electrode, 27% higher than for the nickel electrode and 40% higher than for the copper electrode. The roughness obtained for the nickel electrode was much higher than for the other (employed) electrodes; in order decreasing roughness: tin, copper and aluminium. The variations observed in the silicon etching processes are caused by variations in the secundary electron emission and by the different reaction of the gas (S\'F IND. 6\') with the electrode material, which cause consumption or liberation of fluor in the system. (AU) | |