Magnetron discharge

Therefore, considerable efforts were made on deposition in the transition mode of the reactive magnetron discharge, where nonstable conditions are used and where closed-loop feedback control is mandatory for process stabilization. 

Qualitatively, this observation can be attributed to the high Zn vapor pressure. Once a critical substrate temperature is exceeded, sputtering at a low reactive gas partial pressure leads to the desorption of excess Zn, so the deposition rate is limited by the reactive gas partial pressure p(0<2) as described earlier. Table 5.4 shows that the Zn vapor pressure at a substrate temperature of 300°C is still too low to explain the observed relationship. The Zn desorption is, however, supported by the intensive, high-energy ion bombardment of the MF excited magnetron discharge [38], so that desorption already takes place at lower substrate temperatures. 

At relatively high chamber pressure (P 1 Pa) the partial aggregation of reagents is observed in the plasma of magnetron discharge. 

It is important to recognize that all surfaces that contact with the luminous gas phase participate and influence LCVD operation. Therefore, in principle, in a batch operation, the first run with clean reactor wall could not be replicated in the second run with contaminated reactor wall. Thus, it is necessary to include the step for cleaning the reactor. If only hydrocarbons were used in an LCVD, the cleaning could be done by O2 discharge prior to the normal LCVD operation. (The influence of wall contamination was described in Chapter 10.) In this respect, the effort to minimize the deposition on nonsubstrate surfaces is important even in batch operation of LCVD. Magnetron discharge is quite effective in this respect, as described in Chapter 14. 

Magnetron Discharge for Luminous Chemical Vapor Deposition... 

Important and interesting questions that arise from the magnetron discharge described in the previous chapter are as follows ... 

Cathodic magnetron discharge (CM-A), where the cathode magnetron (CM) is used against a planar electrode without magnetron (A). 

Anode magnetron discharge (C-AM), where a planar cathode without magnetron (C) is used against a magnetron anode (AM). 

---