We developed optical emission spectroscopy based end-point detection techniques for GaAs-based etching in inductively coupled BCl 3 /N 2 plasmas. It was found that an emission peak of Ga ͑417 nm͒ was quite useful as a tracer for in situ process monitoring during both AlGaAs/GaAs and InGaP/GaAs multilayer etching. The intensity of the Ga emission peak increased significantly during AlGaAs/GaAs etching in a BCl 3 /N 2 inductively coupled plasma when the GaAs layer was exposed to the plasma. We found the same result with InGaP/GaAs etching. Utilization of the Ga peak signal is very important during the plasma process for GaAs-based device fabrication, especially for high electron mobility transistors and heterojunction bipolar transistors in order to minimize overetch time during the nonselective etching. The technique provides a breakthrough for in situ end-point detection of GaAs-based nonselective plasma etching.

This paper proposes an updated transformer model for solenoidal inductively coupled plasma sources that can be applied even in low electron density regions. The proposed model can handle plasma in a finite geometry where the electric fields propagating from each boundary overlap, employing a simple analytic expression of the electric field, a one-dimensional (1D) sine hyperbolic function. Based on this field expression, all circuit elements of the transformer model that depend on the electron density, namely, plasma resistance, magnetic inductance, and mutual inductance, can now be obtained. Comparison of absorbed power as well as the circuit elements calculated using the proposed model, named here as the 1D transformer model, shows good agreement with the electromagnetic model, which is known for being quite accurate for cold plasma not only in high but also in low electron density regions. Results also indicate that the 1D transformer model is not limited to a specific setup but rather can be applied in a wide range of discharge conditions.

Animal welfare during transport became an largely issue because of increasing demand for improved animal welfare standards. Most studies on the animal welfare during transportation have concentrated on the atmosphere and the temperature of the truck compartments. Thus, the objective of study was to collect and quantify three axis acceleration and determine the effect of bedding for transporting pigs from farm to slaughterhouse. A total of 2,840 crossbred fattening pigs with a live weight of approximately 115 kg were used. They were raised in the same commercial farms and transported to the same commercial slaughterhouse. A 3×2×2 completely randomized factorial design was used to investigate effects of rubber type bedding (bedding or non-bedding) and two levels of driving style (aggressive or normal) in three different time periods with different outside temperatures. Air temperature treatments were as follow: high temperature ([HT] higher than 24°C); low temperature ([LT] lower than 10°C); normal temperature ([NT] 10°C to 24°C). In our experiment, pigs transported under aggressive driving style showed lower ( p < 0.05) pH and water holding capacity (WHC) than those transported under normal driving style. Pigs transported under normal driving style showed a lower percentage of drip loss (DL) ( p < 0.05) than those transported with an aggressive driving style. Also, transported with bedding showed higher ( p < 0.05) lying behavior but lower ( p < 0.05) sitting behavior than those transported without bedding. Pigs transported under normal driving style showed lower ( p < 0.05) cortisol level than those transported under aggressive driving style. In conclusion, aggressive driving style cause acute stress in pigs, while bedding helps alleviate acute stress in pigs during transportation in LT.