Apparatus for mixing liquids in a certain ratio
First Claim
1. A liquid dispenser comprising:
- a self-lubricating plastic container;
liquid level sensing means for sensing levels of a liquid supplied in said container;
liquid dispensing means for dispensing the liquid from said container in a quantity corresponding to a capacity of said container; and
automatic liquid supply means for automatically supplying the liquid from a chemical tank to said container.
3 Assignments
0 Petitions
Accused Products
Abstract
An apparatus for mixing a deionized water and a hydrofluoric acid precisely in the ratio of 100:1, so as to produce a mixture which are properly used in etching wafters. The mixing apparatus comprises a self-lubricating plastic container of a double construction which enables to obtain a more precise quantity of liquid. The mixing apparatus also comprises an electronic balance measuring the weight of the liquid mixture, an indicator indicating numerically the weight measured by the balance, a mixing tank mixing the liquids, and control valves supplying the liquids in large and small quantities, respectively. According to this arrangement, it is possible to obtain a mixture of a large quantity liquid or a small quantity liquid in a precise mixing ratio with a tolerance of within 1%. Thereby, any poor etching of wafers can be avoided.
28 Citations
10 Claims
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1. A liquid dispenser comprising:
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a self-lubricating plastic container; liquid level sensing means for sensing levels of a liquid supplied in said container; liquid dispensing means for dispensing the liquid from said container in a quantity corresponding to a capacity of said container; and automatic liquid supply means for automatically supplying the liquid from a chemical tank to said container. - View Dependent Claims (2, 3, 4, 5)
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6. An apparatus for mixing two liquids in a predetermined mixing ratio, comprising:
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a liquid dispenser that includes (a) self-lubricating plastic container, (b) liquid level sensing means for sensing levels of a liquid supplied in said container, (c) liquid dispensing means for dispensing liquid from said container in a quantity corresponding to a capacity of said container, and (d) automatic liquid supply means for automatically supplying liquid from a chemical tank to said container; mixing means for mixing precisely the liquids in the precise predetermined mixing ratio; liquid mixture draining means for draining the liquid mixture from said mixing means; and control means for controlling said previously mentioned means. - View Dependent Claims (7, 8, 9)
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10. An apparatus for mixing a combination of liquid chemicals in a predetermined ratio, including
a first liquid dispenser for dispensing a predetermined amount of a first liquid; -
a second liquid dispenser for dispensing a predetermined amount of a second liquid; and mixing means for mixing said first and second liquids;
wherein said first liquid dispenser comprisesan outer container; a dispensing container located within said outer container, an upper edge of said dispensing container being formed with a plurality of spaced recesses; supply means for supplying said first liquid to both said outer container and said dispensing container; liquid sensor means for determining whether said first liquid in said first liquid dispenser is at a first, second or third predetermined level; first delivery means for delivering said first liquid contained within said dispensing container to said mixing means; and second delivery means for delivering said first liquid contained within said outer container back to said supply means; wherein said supply means provides said first liquid until said first level is attained; said second delivery means drains said first liquid until said second level is reached, such that said first liquid contained with in said dispensing container is at said third level; said first delivery means drains an amount of liquid from said dispensing container corresponding to said third level, and delivers said amount to said mixing means.
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Specification