Siltronic Ag

Masashi Uchibe

Teruo Haibara

Yoshihiro Mori

Etsuko Kubo

Etsuko Tanabe

A cleaning method for cleaning an object involves disposing the object in a cleaning liquid held in a cleaning tank; and ultrasonically vibrating the cleaning liquid via an intermediate medium in contact with the cleaning tank, wherein the ultrasonically vibrating includes: ultrasonically vibrating the cleaning liquid with a first difference between respective sonic velocities allowable in the cleaning liquid and the intermediate medium; and ultrasonically vibrating the cleaning liquid with a second difference between the respective sonic velocities allowable in the cleaning liquid and the intermediate medium, wherein the second difference is different from the first difference.

Ultrasonic cleaning method

An ultrasonic cleaning method for cleaning an object in a liquid in which a gas is dissolved includes preparing the liquid in which the gas is dissolved and stirring the liquid while irradiating the liquid with the ultrasonic waves so as to realize a state where bubbles containing the gas dissolved in the liquid continue to be generated. The object is cleaned in the state where the bubbles containing the gas continue to be generated.

Ultrasonic cleaning method and ultrasonic cleaning apparatus

A cleaning method involves: disposing in a cleaning liquid held in a cleaning tank an object to be cleaned; and ultrasonically vibrating the cleaning liquid via an intermediate medium in contact with the cleaning tank to clean said object, the ultrasonically vibrating involving: ultrasonically vibrating the cleaning liquid with the cleaning liquid and the intermediate medium allowing sonic velocities, respectively, having a first difference; and ultrasonically vibrating the cleaning liquid with the cleaning liquid and the intermediate medium allowing sonic velocities, respectively, having a second difference different from the first difference.

An ultrasonic cleaning method for cleaning an object in a liquid in which a gas is dissolved includes preparing the liquid in which the gas is dissolved. The object is cleaned while applying ultrasonic waves to the liquid so that a ratio determined by dividing a vibration strength of the liquid at a fourth-order frequency of the ultrasonic waves by a vibration strength of the liquid at a fundamental frequency of the ultrasonic waves is larger than 0.8/1000.

A dissolved nitrogen concentration monitoring method is used for monitoring a dissolved nitrogen concentration of a cleaning liquid when an ultrasonic wave is irradiated onto the cleaning liquid in which a substrate is dipped. The method includes measuring an amount of increase of a dissolved oxygen concentration of the cleaning liquid resulting from an oxygen molecule generated from a water molecule as a result of a radical reaction caused by ultrasonic wave irradiation. A dissolved nitrogen concentration of the cleaning liquid is calculated from the measured amount of increase of dissolved oxygen concentration based on a predetermined relationship between a dissolved nitrogen concentration and an amount of increase of dissolved oxygen concentration.

Dissolved nitrogen concentration monitoring method, substrate cleaning method, and substrate cleaning apparatus

A calibration method for calibrating a measurement device for measuring a concentration of a gas dissolved in a liquid includes varying the concentration of the gas dissolved in the liquid, and predetermining, as a reference concentration, a concentration of the gas at which an intensity of luminescence produced when the liquid is irradiated with ultrasonic waves shows a peak. The liquid is illuminated with ultrasonic waves while varying the concentration of the gas in the liquid and a measured value is measured, using the measurement device, as a concentration of the gas in the liquid when the intensity of the luminescence shows a peak. The measurement device is calibrated based on the measured value and the reference concentration.

Growing community of inventors

Hikari, Japan

Masashi Uchibe