Method of fabricating a semiconductor device
AssigneeSanyo Electric Co., Ltd.
InventorsMotoyuki Tsuihiji, Hirofumi Iinuma
Life of this patent
Estimating the term…
Abstract
Waste water generated by processing a semiconductor is filtered to be cleaned. Removable matters trapped by a first filter film are used as a second filter film. Filtering capciity is maintained by applying an external force such as bubbles to the second filter film. When removable matters are mixed with the filtered water, the filtered water is recirculated again to the tank in which the waste water is stored, and after it is checked that a desired inclusion rate has been reached filtration is started again.
Claims7
A method for fabricating a semiconductor ingot comprising:
- discharging, to a waste tank, not only water but also Si particle generated by machining a crystal ingot into a wafer or machining a semiconductor wafer;
- adjusting waste water in said waste water tank to a predetermined density by using a filter device;
- transferring said waste water having said predetermined density to collection means;
- discharging said waste water under pressure;
- using said collection means to generate a block that comprises said Si particle at a predetermined water content and that does not react with a chemical in said waste water tank;
- and
- using said block comprising said Si particle as a material to be melted for recycling.
A method for fabricating a semiconductor ingot comprising:
- discharging, to a waste tank, not only water but also Si particle generated by machining a crystal ingot into a wafer or machining a semiconductor wafer;
- adjusting waste water in said waste water tank to a predetermined density by using a filter device;
- transferring said waste water having said predetermined density to collection means;
- discharging said waste water under pressure;
- using said collection means to generate a block that comprises said Si particle at a predetermined water content and that does not react with a chemical in said waste water tank;
- and
- using said block comprising said Si particle as a material to be melted for recycling,
- wherein machining comprises abrading, grinding, polishing, or dicing.
A method for fabricating a semiconductor ingot comprising:
- discharging, to a waste tank, not only water but also Si particle generated by machining a crystal ingot into a wafer or machining a semiconductor wafer;
- adjusting waste water in said waste water tank to a predetermined density by using a filter device wherein a solid composed of the same material as said Si particle is formed as a second filter on the surface of a first filter;
- transferring said waste water having said predetermined density to collection means;
- discharging said waste water under pressure;
- using said collection means to generate a block that comprises said Si particle at a predetermined water content and that does not react with a chemical in said waste water tank;
- and
- using said block consisting of said Si particle as a material to be melted for recycling.
Dependencies are inferred from the claim text.