• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.336-340
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• 2012

Wide band gap p-type hydrogenated amorphous silicon oxide (a-SiO:H) buffer layer has been used at the interface of transparent conductive oxide (TCO) and hydrogenated amorphous silicon (a-Si:H) p-type layer of a p-i-n type a-Si:H solar cell. Introduction of 5 nm thick buffer layer improves in blue response of the cell along with 0.5% enhancement of photovoltaic conversion efficiency (η). The cells with buffer layer show higher open circuit voltage (Voc), fill factor (FF), short circuit current density (Jsc) and improved blue response with respect to the cell without buffer layer.

• Applied Science and Convergence Technology
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• v.25 no.2
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• pp.28-31
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• 2016

The structural and the electronic properties of pentacene on modified Si (001) were investigated using scanning tunneling microscopy (STM), atomic force microscopy (AFM) and ultraviolet photoelectron spectroscopy (UPS). Dodecane was used to modify Si (001) substrates and then pentacene was deposited on dodecane/Si (001). Our STM results show a uniform distribution of aggregated dodecane molecules all over the clean Si (001). The surface structure of pentacene on dodecaene/Si (001) examined by AFM is analogous to that of pentacene on $SiO_2$. The UPS data showed that the work function of pentacene on clean Si (001) and pentacene on modified Si (001) with dodecane was 6.41 and 5.57 eV, respectively. Our results prove that dodecane results in the work function difference between pentacene on clean Si (001) and pentacene on dodecane/Si (001).

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.5
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• pp.729-736
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• 1990

Oxide (RTO), nitrided-oxide(NO), and reoxidized-nitrided-oxide(ONO) films were formed by sequential rapid thermal processing. The film composition was investigated by Auger electron spectroscopy(AES). The Si/SiO2 interface and SiO2 surface are nitrided more preferentially than SiO2 bulk. When the NO is reoxidized, [N](atomic concentration of N) in the NO film decreased` especially, the decrease of [N] at the surface is considerable. The weaker the nitridation condition is, the larger the increase of thickness is as the reoxidation proceeds. The elelctrical characteristics of RTO, NO, and ONO films were evaluated by 1-V, high frequency (1 MHz) C-V, and high frequency C-V after constant current stress. The ONO film-which has 8 nm thick initial oxide, nitrided in NH3 at 950\ulcorner for 60 s, reoxidized in O2 at 1100\ulcorner for 60 s-shows good electrical characteristics such as higher electrical breakdown voltage and less variation of flat band voltage under high electric field than RTO, and NO films.

• Korean Journal of Materials Research
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• v.10 no.10
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• pp.665-670
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• 2000

Linear annealing method was developed to increase the bond strength of Si wafer pair mated at room tem­perature instead of conventional furnace annealing method. It has been known that the interval of the two mating wafer surfaces decreases and the density of gaseous phases generated at the interface increases with increase in an-nealing temperature. The new annealing method consisting of one heat source and light reflecting mirror used these two phenomena and was applied to Si$\mid$$\mid$Si and Si$\mid$$\mid$$SiO_2/Si$ bonding. The bonding interface observed directly by using IR camera and HRTEM showed clear bonding interface without any unbonded areas except the area generated by the dusts inserted into the mating interface at the room temperature. Crack opening method and direct tensile test was ap­pplied to measure the bond strength. The two methods showed similar results. The bond strength increased continuous­tly with the increase of annealing temperature.

• Journal of IKEEE
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• v.22 no.4
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• pp.1230-1233
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• 2018

$Al_2O_3$ films with the thickness of 50 nm were fabricated on 4H-SiC by aerosol deposition, and their electrical properties were characterized with different post annealing conditions. As a result, the $Al_2O_3$ film annealed in $N_2$ atmosphere showed decreased fixed charge density at the interface area between the $Al_2O_3$ and SiC, and increased leakage currents due to the generation of oxygen vacancies. From this result, it was confirmed that proper $N_2$ and $O_2$ ratio for the post annealing process is important.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.865-870
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• 2003

The MFIS (Metal-Ferroelectric-Insulator-Semiconductor) capacitors were fabricated using a metalorganic decomposition method. Thin layers of CeO$_2$ were deposited as a buffer layer on Si substrate and BLT thin films were used as a ferroelectric layer. The electrical and structural properties of the MFIS structure were investigated. X -ray diffraction was used to determine the phase of the BLT thin films and the quality of the CeO$_2$ layer. The morphology of films and the interface structures of the BLT and the CeO$_2$ layers were investigated by scanning electron microscopy. The width of the memory window in the C-V curves for the MFIS structure is 2.82 V. The experimental results show that the BLT-based MFIS structure is suitable for non-volatile memory FETs with large memory window.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.11
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• pp.869-873
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• 2001

The effects of alternate bias stress on p-channel poly-Si TFT\`s has been systematically investigated. We alternately applied positive and negative bias stress on p-channel poly-Si TFT\`s, device Performance(V$\_$th/, g$\_$m/, leakage current, S-slope) are alternately appeared to be increasing and decreasing. It has been shown that device performance degrade under the negative bias stress while improve under the positive bias stress. This effects have been related to the hot carrier injection into the gate oxide rather than the generation of defect states within the poly-Si/SiO$_2$ interface under alternate bias stress.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.1
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• pp.70-77
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• 2019

$SiO_x$ nanoparticles were granulated, and their microstructures and effects on electrochemical behaviors were investigated. In spite of the promising electrochemical performance of $SiO_x$, nanoparticles have limitations such as high surface area, low density, and difficulty in handling during slurry processing. Granulation can be one solution. In this study, pelletizing and annealing were conducted to create particles with sizes of several decades of micron. Decrease in surface area directly influences the initial charge and discharge process when granules are applied as anode materials for Li-ion batteries. Lower surface area is key to decreasing the amount of irreversible phase-formation, such as $Li_2Si_2O_5$, $Li_2SiO_3$ and $Li_4SiO_4$, as well as forming the solid electrolyte interface. Additionally, aggregation of nanoparticles is required to obtain further enhancement of the electrochemical behavior due to restrictions that there be no $Li_4SiO_4$-related reaction during the first discharge process.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.1
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• pp.102-109
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• 1987

This study is carrier out to investigate the carrier injection and the characteristics of trapping for the CVD deposited Al2O3 film on Si substrates. Samples used are metal -Al2O3-Si Structure in which metal field plates are used with Aluminium or God. Canier injection and trapping, which result in flat band voltalge shift, occur at fields as low as 1~2 MV/cm. An approximate method is proposed for computing the location of the centroid of the trapped electrons in this paper. Results show that carriers are trapped near the injecting interface at fields less than about 5MV/cm. Because of continued charging, a steady state can not be reached. Therefore the unique I-V curve is obtained when the traps are initially empty. By utilization of applied voltage on each point of the fresh device sample, it is measured the I-V surves for two polarities of applied voltage. The current densities observed in the Al2O3 films are much larger than those obtained in SiO2.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.7
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• pp.73-81
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• 1992

We have investigated the thermal reaction property and the oxygen behavior of TiN/Ti/Si structure after different hear treatments using x-ray photoelectron spectroscopy and cross-sectional transmission electron microscopy measurements. During the heat treatment in N$_2$ amibient, the considerable amount of oxygen atoms incorporates into TiN/Ti/Si Structures. It is found that oxygen atoms pile up at the top surface of TiN and TiN/Ti interface, forming a compound of TiO$_2$ above $600^{\circ}C$. Inside the TiN film, the oxygen content increases as the annealing temperature increases, mostly TiO and Ti$_2$O$_3$ rather than thermodynamically stable TiO$_2$. Above the annealing temperature of 55$0^{\circ}C$, the TiSi$_2$ formation has initiated. One thing to note is that a severe blistering is observed in the sample annealed at $600^{\circ}C$, due to (1) the difference of thermal expansion coefficient between TiN and Si` (2) the compressive stress induced by the volume reduction caused by the Ti-Silicide grain while elevating temperatures.