Voltage waveform generator for plasma assisted processing apparatuses
AssigneeProdrive Technologies Innovation Services B.V.
InventorsJordi Everts, Noud Slaats
Life of this patent
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Abstract
A voltage waveform generator for a plasma assisted processing apparatus includes a common node, a voltage supply circuit operable to switch between at least two voltage levels at a first switch node, a first inductor connected between the first switch node and the common node, and a control unit configured to operate the voltage supply circuit.
Claims21
A voltage waveform generator for a plasma assisted processing apparatus, the voltage waveform generator comprising:
- a first switch node and a common node,
- a voltage supply circuit connected to the first switch node and operable to switch between at least two voltage levels at the first switch node,
- a first inductor connected between the first switch node and the common node,
- a control unit configured to operate the voltage supply circuit so as to obtain a predetermined voltage waveform at the common node, and
- a voltage clamping circuit coupled to the common node and operable to clamp a voltage of the common node at a predetermined level.
A method of generating a voltage waveform for a substrate subjected to plasma assisted processing, the method comprising:
- applying a switched voltage to a switch node, the switch node connected to a common node via an inductor, the common node electrically coupled to the substrate, wherein the switched voltage causes a first current to flow through the inductor, and wherein the first current through the inductor defines a ramp up and a ramp down of a voltage pulse of the voltage waveform, and
- clamping a voltage at the common node to a clamping voltage level while an absolute value of the first current is substantially zero during a clamping period.
A voltage waveform generator for a plasma assisted processing apparatus, the voltage waveform generator comprising:
- a first switch node and a common node,
- a voltage supply circuit connected to the first switch node and operable to switch between at least two voltage levels at the first switch node,
- a first inductor connected between the first switch node and the common node,
- a control unit configured to operate the voltage supply circuit so as to obtain a predetermined voltage waveform at the common node, and
- a voltage clamping circuit coupled to the common node, wherein the voltage clamping circuit is configured to provide a switchable connection between the common node and a voltage node of the voltage supply circuit, the voltage node configured for providing one of the at least two voltage levels.
Dependencies are inferred from the claim text.