Method for surface treatment of silicon based substrate
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKiyoshi Arita, Tetsuhiro Iwai, Hiroshi Haji, Shoji Sakemi
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Abstract
A surface treatment method for thinning a silicon based substrate obtains a milky-dull color on an overall surface uniformly of the silicon based substrate. To be more specific, a surface opposite to a circuit-formed surface is mechanically polished, then the surface is etched using inert gas such as argon gas for producing plasma. This etching forms micro dimples uniformly on the surface. Next, the surface is further etched using fluorine based gas for producing plasma. This etching obtains a milky-dull color uniformly on the surface. As a result, printed marks on the surface can be read with ease, and pick-up errors in die-bonding can be reduced.
Claims7
A method of surface treatment of a silicon based substrate with plasma, said method comprising the steps of:
- performing a first plasma etching for forming fine dimples on a first surface of said silicon based substrate, said first surface of said silicon based substrate being opposite a second surface of said silicon based substrate on which circuit elements are formed;
- and
- performing a second plasma etching for further etching the surface of the fine dimples with plasma produced by gas including fluorine.
Dependencies are inferred from the claim text.