Methods for processing semiconductors to reduce surface particles
AssigneeSemitool, Inc.
InventorMichael K. Jolley
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Abstract
Methods for removing particulates from the surfaces of semiconductor materials, such as silicon substrates and wafers. The methods use repeated oxide growth steps and intervening oxide removal. Rinses are preferably used between the oxide growth and removal steps, such as with purified water. The oxide growth steps use an oxidation agent and a base, for example hydrogen peroxide and ammonium hydroxide. The oxide removal steps use a suitable oxide removal agent such as a hydrogen halide acid, for example hydrogen fluoride.
Claims21
A method for processing a surface of semiconductor material using liquids to remove particles therefrom, characterized by:
- a) treating said surface using an oxide growth liquid to perform an oxide growth step in which an increased thickness of semiconductor oxide is formed along the surface;
- said oxide growth liquid including a suitable oxidation agent;
- b) treating said surface using an oxide removal liquid to perform an oxide removal step in which semiconductor oxide is removed to provide a decreased thickness of semiconductor oxide along said surface;
- c) maintaining a semiconductor oxide layer upon the surface throughout steps a) and b) to prevent the surface from becoming hydrophobic;
- d) treating said surface at least a second time using an oxide growth liquid to perform at least a second oxide growth step in which an increased thickness of semiconductor oxide is formed along the surface;
- said oxide growth liquid including a suitable oxidation agent;
- e) treating said surface at least a second time using an oxide removal liquid to perform an oxide removal step in which semiconductor oxide is removed to provide a decreased thickness of semiconductor oxide along said surface;
- f) maintaining a semiconductor oxide layer upon the surface throughout steps d) and e) to prevent the surface from becoming hydrophobic.
Dependencies are inferred from the claim text.