Reactor environment, plasma

If growing species stray from the active LCVD environment, they will deposit on the reactor walls, which is out of the luminous gas phase, as oligomers (not polymers). The presence of oligomer deposition on the reactor walls could cause serious interference with subsequent plasma polymerization, which is carried out in a contaminated reactor. 

Steps 2-4 were carried out in a vacuum reactor consecutively. Thus, the plasma reactor follows the cycle (1) pump down from ambient environment (2) O2 plasma (3) TMS plasma (4) HFE plasma (5) exposure to ambient air. The sequences of plasma processes are O2/TMS, TMS/HFE, and HFE/O2, or can be expressed -(02/TMS/HFE/)-. 

The plasma phase chemistry is most easily illustrated for a Freon 14 (CF4) feed gas and provides the proto-type for understanding the processes in the plasma phase. The plasma chemistry must perform two tasks. First, it must generate the etching species and second, it must provide one or more additional electrons to sustain the plasma environment, as electrons are continually lost due to collisions with the walls of the reactor, recombination with positively charged ions, and flow out of the reactor towards... 

The lAMS technique is applied in a simulation study of a diamond CVD reactor [93], It is most advantageous when the experimenter does not know a priori what species to expect. A second advantage is its adaptability to a wide variety of process environments. To simulate the reacting plasma environment, a sampling aperture, followed by the skimmer, is fixed at the center of the growth substrate (Fig. 5.8). Mass spectra were obtained (Fig. 5.9) with plasma activation in two modes (i)... 

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