Chemical concentration control device for semiconductor processing apparatus

• US 20030095472A1
• Filed: 11/12/2002
• Published: 05/22/2003
• Est. Priority Date: 11/19/2001
• Status: Active Grant

• Current Assignee: KAIJO Corporation (Shibuya Corporation)
• Original Assignee: KAIJO Corporation (Shibuya Corporation)
• Inventors: Fukui, Akira
• Granted Patent: US 6,921,193 B2
• Time in Patent Office: Days
• US Class Current: 366/152.1
• CPC Class Codes: B01F 2101/58 Mixing semiconducting materials, e.g. during semiconductor or wafer manufacturing processes
• CPC Class Codes: B01F 35/213 of the properties of the mixtures, e.g. temperature, density or colour
• CPC Class Codes: B01F 35/2132 Concentration, pH, pOH, p(ION) or oxygen-demand B01F35/2133 takes precedence
• CPC Class Codes: B01F 35/2202 Controlling the mixing process by feed-back, i.e. a measured parameter of the mixture is measured, compared with the set-value and the feed values are corrected
• CPC Class Codes: B01F 35/2211 Amount of delivered fluid during a period

Abstract

A chemical concentration control device for a semiconductor processing apparatus being capable of keeping processing chemicals at constant concentrations, and of maintaining the liquid level required for processing is provided. A semiconductor processing apparatus includes a concentration measuring unit, a drift observation unit, a replenishment quantity calculating unit, a concentration estimating unit, a fixed-quantity replenishment processing unit, and a replenishment control unit for controlling replenishment of chemicals based on the replenishment quantities calculated by the fixed-quantity replenishment processing unit, so that the replenishment quantity calculating unit calculates the replenishment quantities of the respective chemicals with respect to the predetermined reference replenishment quantity based on data measured by the concentration measuring unit and the drift observation unit, and estimated concentration data supplied from the concentration estimating unit.

Claims

1. A chemical concentration control device for a semiconductor processing apparatus comprising:

a concentration measuring unit for measuring chemical concentrations;

a drift observation unit for observing the drift amount of concentrations after the overhead time of the concentration feedback control system has elapsed;

a replenishment quantity calculating unit for calculating the replenishment quantities of chemicals;

a fixed-quantity replenishment processing unit for processing the replenishment quantity of each chemical so that the summation of the replenishment quantities of respective chemicals obtained by the replenishment quantity calculating unit becomes equal to the predetermined reference replenishment quantity;

a concentration estimating unit for estimating concentrations to be achieved after chemicals have replenished by the replenishment quantities calculated by the fixed-quantity replenishment processing unit; and

a replenishment control unit for controlling replenishment of chemicals based on the replenishment quantities calculated by the fixed-quantity replenishment processing unit.

2. A chemical concentration control device for a semiconductor processing apparatus according to claim 1, wherein the replenishment quantity calculating unit calculates the replenishment quantities of chemicals based on concentration data measured by the concentration measuring unit, the drift amount of concentration observed by the drift observation unit, and estimated concentration data estimated by the concentration estimating unit.

3. A chemical concentration control device for a semiconductor processing apparatus according to claim 1, wherein the fixed-quantity replenishment processing unit of the chemical concentration control device for a semiconductor processing apparatus calculates the replenishment quantities of chemicals based on the priority for chemical replenishment.

4. A chemical concentration control device for a semiconductor processing apparatus according to claim 1, wherein the replenishment control unit of the chemical concentration control device for a semiconductor processing apparatus replenishes chemicals when the liquid level of chemical is lowered to a position below the predetermined level.