Abstract: An apparatus for measuring the water content of a water-containing liquid mixture contained in a tight chemistry tank includes a heating device for controlling the temperature of the liquid mixture to a temperature near the boiling point of the liquid mixture, a cooling medium system disposed at the top of the tight chemistry tank having a cooling medium inlet and a cooling medium outlet, a temperature measurement system for determining the temperature difference between the cooling medium inlet and outlet, and a computing device for calculating the water content of the liquid mixture from the temperature difference. Also provided is a tank for supplying water to the liquid mixture, and a control system for adjusting the amount of water supplied from the tank based upon the water content measured by the measuring apparatus. Also provided is a method for measure the water content.

Abstract: A recycling procedure for 300 mm nitride dummy wafers which have a stabilization layer of silicon dioxide is provided. The recycling procedure is essentially based on selectively wet etching the deposited silicon nitride with respect to the silicon dioxide stabilization layer, preferably with hot phosphoric acid at 160° C. In particular, a method of handling a silicon wafer which is employed as a dummy wafer during a nitride deposition process includes the steps of depositing a silicon dioxide layer on the wafer surface, performing the nitride deposition process on the wafer to deposit silicon nitride or silicon oxinitride on the wafer surface until a predetermined layer thickness is reached, and etching the silicon nitride or silicon oxinitride layer selectively with respect to the silicon dioxide layer.

Abstract: An apparatus for measuring the water content of a water-containing liquid mixture contained in a tight chemistry tank includes a heating device for controlling the temperature of the liquid mixture to a temperature near the boiling point of the liquid mixture, a cooling medium system disposed at the top of the tight chemistry tank having a cooling medium inlet and a cooling medium outlet, a temperature measurement system for determining the temperature difference between the cooling medium inlet and outlet, and a computing device for calculating the water content of the liquid mixture from the temperature difference. Also provided is a tank for supplying water to the liquid mixture, and a control system for adjusting the amount of water supplied from the tank based upon the water content measured by the measuring apparatus. Also provided is a method for measure the water content.

Abstract: A recycling procedure for 300 mm nitride dummy wafers which have a stabilization layer of silicon dioxide is provided. The recycling procedure is essentially based on selectively wet etching the deposited silicon nitride with respect to the silicon dioxide stabilization layer, preferably with hot phosphoric acid at 160° C. In particular, a method of handling a silicon wafer which is employed as a dummy wafer during a nitride deposition process includes the steps of depositing a silicon dioxide layer on the wafer surface, performing the nitride deposition process on the wafer to deposit silicon nitride or silicon oxinitride on the wafer surface until a predetermined layer thickness is reached, and etching the silicon nitride or silicon oxinitride layer selectively with respect to the silicon dioxide layer.