Options
2008
Conference Paper
Titel
HIPIMS/HPPMS process design with multi channel pulse pattern controller
Abstract
HIPIMS/HPPMS as promising sputter technology uses highly ionized particles to grow thin films from metallic or ceramic targets. [1,2,3,4]. The ionization degree of the plasma is strongly related to the discharge parameters and can be tuned to values higher than 100 percent by producing double and even higher charged ions at elevated discharge current densities of 1 A/cm2 and more. The benefit of the high ionization degree can be seen in the fact that the majority of the particles inside the process chamber is ionized and can contribute to the situation at the substrate surface, where thin films can be grown with new material mixtures and properties. A multi channel pulse pattern controller produced by IfU Diagnostic Systems GmbH is used to control the pulse power supply, which drives single or double magnetro in a modified industrial deposition chamber. The magnetic field strength of the magnetrons was increased to achieve a better HIPIMS/HPPMS performance. Each of the controllers pulse pattern output is capable to drive an industrial pulse unit which is equipped with digital input. The pulse patterns easily can be edited by PC based user interaction. All of the pulse pattern parameters like on-time, off-time, number and position of the pulses as well as the position of the sync pulse can be adjusted by the user in time steps of 0.1 microsecond. Positive and negative unipolar and also bipolar discharge modes could be established by only changing the pulse patterncontroller settings. Pulse voltage and current are recorded by the high speed ADC channels of the pulse pattern controller. A process control can be established by use of a medium speed ADC channel, which is used to influence the pulse pattern depending from the actual state of the discharge. Several very different pulse modes are show as example. Time resolved optical emission data are captured synchronously to the pulse discharge by use of an AOS µchron optical emission spectrometer produced by IfU Diagnostic Systems GmbH. Selected optical emission data are shown in relation to the pulse pattern generated by the pulse pattern controller.