Patent ID: 10008369

Abstract:
There is provided an apparatus for cyclical plasma etching of a substrate, the apparatus comprising: a process chamber; a support within the process chamber for receiving the substrate to be etched; a controller for repeatedly applying a dosing step and a bombardment steps respectively; a dosing controller for controlling the flow of a process gas in the dosing step such that the substrate is exposed to a maximum dose of process gas in use of 1000 Langmuirs and said dose is controllable within an accuracy of 1 Langmuir; and a first signal generator coupled to the process chamber and a second signal generator coupled to the support within the process chamber, the first and second signal generators being configured such that in use positions ions of an plasma active species within the process chamber have a substrate bombardment energy in the range of 10 eV to 100 eV which is controllable within an accuracy of 5 eV. There is also provided a method for cyclical plasma etching of a substrate using said apparatus.