Gas flow control is important factor that influences the concentration of process gas and the pressure of the process chamber. In manufacturing processes that use metal organic (MO) gases, a system that controls the flow rate of MO gas must be developed to improve film performance and the reliability of film formation. We have developed a high temperature flow control system based on pressure measurements (HT-FCS) to control the flow rate of MO gas. Moreover, a liquid source control system that combines a HT-FCS and vaporizer was developed. Using this system, it was possible to control the flow rate of MO gas with high accuracy for extended periods. A flow control system that can supply MO gas with a stable flow rate by vaporizing MO material with the quantity needed at each time has been realized.

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We have been studying in-line gas concentration sensor units for various metal-organic(MO) gases used in electronic device manufacturing process. MO gases are low vapor pressure and are generally supplied by bubbling. At the time of bubbling supply, concentration control is performed by internal pressure control and feedback control by in-line gas concentration sensor units for concentration correction due to lowering of the liquid level inside the MO tank. We have evaluated a high sensitivity in-line gas concentration sensor that adopts ultraviolet absorption method and charge amplifier detection circuit and demonstrated that it is a unit with high response speed of 400 msec or less and high detection sensitivity. In this report, we confirmed that it is possible to measure the concentration of Zr, Hf type MO gas used for semiconductor gate insulating film.

This work presents a high-sensitivity, real-time, compact gas concentration sensor using a time-sharing dual-wavelength UV light absorption method developed for a high-precision trimethyl aluminum (TMA) gas supply system. We analyzed the characteristics of TMA, examined a method to increase sensitivity by controlling the gas transition, and fabricated a highly reliable heatable gas cell. The detection circuit demonstrated that TMA can be measured stably using a charge amplifier method that can detect various metal organic gases with high sensitivity. By controlling the sensing temperature to increase the ratio of TMA monomers (which have a higher UV absorbance) to dimers, a detection limit of 62.7 ppm was achieved.

This article presents a global shutter (GS) high signal-to-noise ratio (SNR) and a high-frame-rate CMOS image sensor (CIS) for in situ fluid concentration distribution measurements using absorption imaging. The pixel consists of a ultraviolet (UV)-visible-near infrared (NIR) waveband pinned photodiode (PD) with high robustness against UV light irradiation for various measurement objects, two-stage lateral overflow integration capacitors (LOFIC) for high dynamic range and high SNR, and a voltage-domain memory bank for GS. The developed prototype CIS with 22.4-μm pitch pixels exhibited 69.7-dB maximum SNR, 123-dB dynamic range, and 1000-frames/s maximum frame rate under single exposure GS and successfully captured images of dynamic movement of NO 2 gas concentration distribution in the vacuum chamber for 300-mm-diameter wafers. Index Terms-Absorption imaging, CMOS image sensor (CIS), global shutter (GS), lateral overflow integration capacitor (LOFIC), signal-to-noise ratio (SNR), wide dynamic range (WDR). I. INTRODUCTIONP RACTICAL realization of smart ways of manufacturing, agriculture, and healthcare is critical to improve the productivity and sustainability of our society. In these Manuscript