Method and Apparatus for Cleaning Semiconductor Substrates
AssigneesKatholieke Universiteit Leuven, KU LEUVEN R&D, Imec
InventorsPaul Mertens, Steven Brems, Elisabeth Camerotto, Marc Hauptmann
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Abstract
The present invention is related to a method and apparatus for cleaning a substrate, in particular a semiconductor substrate such as a silicon wafer. The substrate is placed in a tank containing a cleaning liquid, at an angle with respect to acoustic waves produced in said liquid. The angle corresponds to the angle of transmission, i.e. the angle at which waves are not reflected off the substrate surface. A damping material is provided in the tank, arranged to absorb substantially all waves thus transmitted through the substrate. A significant improvement in terms of cleaning efficiency is obtained by the method of the invention.
Claims12
A method for cleaning a substrate (1), comprising the steps of:
- submerging the substrate in a liquid,
- producing acoustic waves in said liquid, said waves propagating in a wave propagation direction,
- orienting the substrate at an angle with respect to said wave propagation direction, said angle being chosen so as to maximize the transmission of said acoustic waves through the substrate,
- substantially absorbing all of said acoustic waves transmitted through said substrate.
Apparatus for cleaning a substrate, comprising:
- a tank (2) suitable for holding a cleaning liquid,
- an acoustic transducer (3) arranged in connection with said tank so as to be able to produce acoustic waves propagating in a cleaning liquid in said tank,
- a holding means for holding and maintaining a substrate (1) in said tank, at an angle to the propagation direction of said waves,
- a layer of damping material (4) placed at least at a location opposite to said transducer (3), with the substrate holding means in between the transducer (3) and the damping material located opposite the transducer.
Dependencies are inferred from the claim text.