Jatmiko Endro Suseno

The depletion influence on the non-planar vertical MOSFET threshold voltage

The continuous scaling of transistors in nano scale leads to the invention of more sophisticated devices which may possess non-planar structures. As a consequence, the model for respective devices is of importance in order to predict the performance and behaviour throughout its operation. In non-planar structure, the thickness of silicon layer strongly affects the overall performance of the device. In this paper, we investigate the influence of depletion in the silicon layer of vertical MOSFET and develop an analytical model for devices with vertical pillar using parabolic approximation. The model for floating body channel structure which may form either partial or fully depleted channel was developed and elaborated as well. The simulation result shows the shift in threshold voltage characteristics with the different depletion widths and pillar thicknesses in the variation of channel length.

Lithology and characteristic of landslide in Gombel Hill by 2D geoelectric resistivity method using dipole-dipole configuration

Gombel hill locates at Semarang, Central Java, Indonesia. Base on Semarangs susceptiblity map zone, Gombel hill is belong to high susceptibility and instability zone. Instability may cause faults to Gombel hill area, unfortunately the geosciences research in Gombel is still lack. The geophysical survey has been conducted using 2D geoelectric resistivity method with dipole – dipole configuration to identify the lithology of landslide at Gombel hill. The data have been collected from three lines. The first and third line have 100 m length, and the second line have 80 m length with 5 m space in each lines. The data were processed and modelled using Res2Dinv software. From the first line, suspected there are two layers which formed the structure of the subsurface. The second line suspected there are three layers which formed the structure of the subsurface. And the last line suspected there are two layers which formed the structure of the subsurface. Overall, the landslide of Gombel hill area can be found with depth 5 m – 6 m and found at contact between clay and clay rock layer. We expect the results can be used for mitigation hazard and planning the developing infrastructure in Gombel area.

Ultrasound–assisted extraction optimization of phenolic compounds from Psidium guajava L. using artificial neural network-genetic algorithm

Artificial Neural Network-Genetic Algorithm (ANN-GA) was used in this work to model the extraction parameters using Ultrasound Assisted Extraction (UAE) in producing phenolic compounds of guava (Psidium guajava L.) leaves. The ANN-GA model was used to evaluate and predict the effect of frequency, temperature, time, and their interaction under optimum conditions. The controlled parameters were frequency (20-40 kHz), temperature (2535 °C), and sonication time (20-40 minutes). Furthermore, the input and output parameters were modeled by LM-back propagation ANN. The optimization variable was then determined by GA. ANN trial and error method was used to determine the bias, weight, and number of hidden layer nodes. The fitness function for optimization with GA used the bias and weight which were obtained from ANN. The prediction of total phenolic on guava leaves using the ANN model shows the mean absolute precentage error value is 13.07. Based on the experiment the optimum conditions were obtained at 40 kHz, 35°C,30 minutes and resulted 589.02 ppm. While ANN-GA model obtained optimum results at 39.79 kHz, 34.83°C, 20 min, then the mean absolute error optimization was 3.46. It can be concluded that ANN-GA model can be used for optimizing the phenolic yields of guava leaves.

Detection of CdSe quantum dot photoluminescence for security label on paper

CdSe quantum dot has great potential in various applications especially for emitting devices. One example potential application of CdSe quantum dot is security label for anti-counterfeiting. In this work, we present a practical approach of security label on paper using one and two colors of colloidal CdSe quantum dot, which is used as stamping ink on various types of paper. Under ambient condition, quantum dot is almost invisible. The quantum dot security label can be revealed by detecting emission of quantum dot using photoluminescence and cnc machine. The recorded quantum dot emission intensity is then analyzed using home-made program to reveal quantum dot pattern stamp having the word ’RAHASIA’. We found that security label using quantum dot works well on several types of paper. The quantum dot patterns can survive several days and further treatment is required to protect the quantum dot. Oxidation of quantum dot that occurred during this experiment reduced the emission intensity of quantum dot patterns.

The Corner Effects of a Curved‐Channel MOSFET

The corner effects of a curved channel MOSFET are proposed. Various several curved channel angles are applied and effects of the corner identified through Devedit TCAD Silvaco. These simulations can understand electrical characteristics and effects of corner if the channel of device is curved, such as grooved gate MOSFET and vertical MOSFET. In this paper, the results show corner effect of the long channel devices can suppress leakage current but giving rise to DIBL, Subthreshold Swing (SS) and threshold voltage (Vth). The effects of corner can suppress short‐channel effects and hot carrier effects, due to the potential barrier generated at the corner region. The device has also high driving current and better controllability of channel since the width of gates are increased, the corner formed by the conterminous gates may affect the electric field and surface potential in the corner region of the channel.