applied microwave frequency, a high degree of dissociation and ionization (10-2 for ECR

compared with 10-6 for RIE) results due to the coupling between the electron energy and

the applied electric field [9]. The ECR creates high density plasma in which the

concentration of charged particles is approximately 1011cm3 [1,3,11]. A high density

plasma can potentially produce higher etch rates because of the increased concentration

of charged particles and typically exhibits less damage than that produced from a reactive

ion etching reactor [1, 11].



 m row es


 magnetic
 cil M







 Slock chamber
 1 I RFI|
 valve


Figure 5. A schematic of the plasma reactor is pictured. Note the circulation of electrons
in the plasma induced by the magnetic coil in the upper region of the etch chamber.

 The reactive ion etching (RIE) part of the reactor consists of a radio frequency

applied to the sample platform acts as a grounded electrode with an area the size of the

reactor chamber. As electrons attach to the sample surface a negative self-bias occurs

which attracts the energetic ions of the plasma to the surface. There is a load lock

chamber where the sample is inserted before being transferred into the etch chamber by