| Discharge plasmas can be ignited by direct current (DC), low to mid-frequency alternating current (AC), radio-frequency (RF), and microwave power sources. In addition to these continuous excitation sources, pulsed excitation, e.g. by bipolar or unipolar DC pulses is also possible. Plasmas in devices which contain insulating (dielectric) surfaces can generally not be sustained by DC power because of the buildup of charges that eventually will cause arcing. Plasma generation using pulsed DC power has emerged as a particularly attractive technique because of the high level of control and versatility afforded by the independent variation of pulse amplitude, pulsing frequency, and duty cycle. In this thesis, we used time-resolved electrical probe measurements and optical diagnostics techniques (emission spectroscopy and imaging) to study the temporal behavior of two plasmas excited by pulsed DC power, low-pressure magnetron plasmas for reactive sputter deposition and high-pressure dielectric barrier discharge plasmas for the generation of ultraviolet (UV) light and reactive radicals. An attempt was made to correlate the macroscopic plasma parameters with the basic collisional and radiative processes in these plasmas. |
