• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.08a
• /
• pp.169-169
• /
• 2010

As display industry requires various applications for future display technology, which can guarantees high level of flexibility and transparency on display panel, oxide semiconductor materials are regarded as one of the best candidates. $InGaZnO_4$(IGZO) has gathered much attention as a post-transition metal oxide used in active layer in thin-film transistor. Due to its high mobility fabricated at low temperature fabrication process, which is proper for application to display backplanes and use in flexible and/or transparent electronics. Electrical performance of amorphous oxide semiconductors depends on the resistance of the interface between source/drain metal contact and active layer. It is also affected by sheet resistance on IGZO thin film. Controlling contact/sheet resistance has been a hot issue for improving electrical properties of AOS(Amorphous oxide semiconductor). To overcome this problem, post-annealing has been introduced. In other words, through post-annealing process, saturation mobility, on/off ratio, drain current of the device all increase. In this research, we studied on the relation between device's resistance and post-annealing temperature. So far as many post-annealing effects have been reported, this research especially analyzed the change of electrical properties by increasing post-annealing temperature. We fabricated 6 main samples. After a-IGZO deposition, Samples were post-annealed in 5 different temperatures; as-deposited, $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$, $400^{\circ}C$ and $500^{\circ}C$. Metal deposition was done on these samples by using Mo through E-beam evaporation. For analysis, three analysis methods were used; IV-characteristics by probe station, surface roughness by AFM, metal oxidation by FE-SEM. Experimental results say that contact resistance increased because of the metal oxidation on metal contact and rough surface of a-IGZO layer. we can suggest some of the possible solutions to overcome resistance effect for the improvement of TFT electrical performances.

• Journal of the Korean Magnetics Society
• /
• v.9 no.4
• /
• pp.210-216
• /
• 1999

The objective of this paper is to investigate corrosion behaviors of CoCrTa/CrNi thin film and post heat-treatment effect. An electron beam evaporator was used for films deposition. After evaporation, post heat-treatment was carried out under $5.0{\times}10^3$ Torr vacuum condition. Annealing temperature and time were 400 $^{\circ}C$ and 30 min, respectively. To understand the effect of annealing on corrosion behavior of CoCrTa/CrNi, potentiodynamic polarization technique and accelerated corrosion chamber test were undertaken. Corrosion potential is higher for the annealed samples (CoCrTa 400$\AA$/CrNi 1000$\AA$) than for as-deposited one. This is attributed to an enrichment of Cr in the surface layer of the thinfilm resulting in a more corrosion resistant material.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.457-458
• /
• 2009

In this work, transparent conducting Al-doped zinc oxide (AZO) films were prepared on Coming glass substrate by RF magnetron sputtering using an Al-doped ZnO target (Al: 2 wt.%) at room temperature and all films were deposited with athickness of 150 nm. We investigated the effects of the post-annealing temperature and the annealing ambient on structural, electrical and optical properties of AZO films. The films were annealed at temperatures ranging from 300 to $500^{\circ}C$ in steps of $100^{\circ}C$ using rapid thermal annealing equipment in oxygen. The thickness of the film was observed by field emission scanning electron microscopy (FE-SEM) and grain size was calculated from the XRD spectra using the Scherrer equation and their electrical properties were investigated using a hole measurement and the reflectance of AZO films was investigated by UV-VIS spectrometry.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.8
• /
• pp.734-739
• /
• 2005

Zinc oxide films were deposited on Si (111) substrates by radio-frequency (rf)sputtering at a room temperature and post annealed in Na, air, and $H_2O$ ambient at temperatures between $800{\circ}C$ for 2 hrs. The properties were investigated by atomic force microscope (AFM), X-ray diffraction (XRD), Auger electron spectroscopy (AES) and photoluminescence (PL). Our experiments demonstrated that ZnO films have the better crystal quality for post thermal annealing and especially in $H_2O$ ambient. Even though thermal annealing reduced deep level emission somewhat, for further getting rid off deep level emission, oxygen contents should be adjusted. In our results, $H_2O$ ambient gave the best structural and optical properties.

• Journal of the Semiconductor & Display Technology
• /
• v.19 no.2
• /
• pp.55-59
• /
• 2020

Copper Oxide (CuO) films were deposited on the n-type silicon wafer by rf magnetron sputtering for heterojunction solar cells. And then the samples were treated as a function of the annealing temperature (300-600℃) in a vacuum. Their electrical, optical and structural properties of the fabricated heterojunction solar cells were then investigated and the power conversion efficiencies (PCE) of the fabricated p-type copper oxide/n-type Si heterojunction cells were measured using solar simulator. After being treated at temperature of 500℃, the solar cells with CuO film have PCE of 0.43%, Current density of 5.37mA/㎠, Fill Factor of 39.82%.

• New & Renewable Energy
• /
• v.17 no.4
• /
• pp.36-45
• /
• 2021

To remove the Cu secondary phase remaining on the surface of a CIGSSe absorber layer manufactured by the two-step process, KCN etching was applied before depositing the CdS buffer layer. In addition, it was possible to increase the conversion efficiency by air annealing after forming the CdS buffer layer. In this study, various pre-treatment/post-treatment conditions wereapplied to the S-containing CIGSSe absorber layerbefore and after formation of the CdS buffer layer to experimentally confirm whether similareffects as those of Se-terminated CIGSe were exhibited. Contrary to expectations, it was noted that CdS air annealing had negative effects.

• Composites Research
• /
• v.26 no.2
• /
• pp.123-128
• /
• 2013

The PVDF (polyvinylidene fluoride) fibers were prepared using the wet spinning processing. To improve ${\beta}$-phase crystalline which closely related piezoelectric property PVDF wet spun fibers conducted post treatment. Post treatment is consisted of heat stretching and annealing process. The heat stretching and annealing conditions were controlled by changing temperature between glass transition temperature and melting temperature. From these experimental data, the resulting crystal structure of the ${\beta}$-phase crystalline was confirmed by FT-IR and XRD experiments. From these analysis results, optimum stretching and annealing conditions of the wet spun PVDF fibers were founded to increase high ${\beta}$-phase crystalline. Furthermore results showed that thermal processing had a direct effect on modifying the crystalline microstructure and also confirmed that heat stretching and annealing could increase the degree of crystallinity and ${\beta}$-phase crystalline. Finally, piezoelectric constant ($d_{11}$) of the post heat treated PVDF fibers reinforced composite were measured to investigate the feasibility for the sensing materials.

• Journal of Sensor Science and Technology
• /
• v.26 no.2
• /
• pp.96-100
• /
• 2017

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been extensively studied as the active material in ammonia gas sensor because of its fast response time, high conductivity and environmental stability. It is well known that a post annealing process for organic devices based on PEDOT:PSS significantly increases the device performance. In this study, we propose the solvent annealing of PEDOT:PSS and investigated its effects. As a results, post solvent annealing on PEDOT:PSS lead to the surface chemical and physical properties change. These changes result in improved conductivity of the PEDOT:PSS. In additional, ammonia sensitivity of solvent annealed PEDOT:PSS become higher than pristine polymer film. The enhancement is mainly caused by the depletion of gas barrier PSS and structural re-forming PEDOT networks. We believe that the post solvent annealing is a promising method to achieve highly sensitivity PEDOT:PSS films for applications in efficient, low-cost and flexible ammonia gas sensor.

• Journal of Magnetics
• /
• v.22 no.1
• /
• pp.7-13
• /
• 2017

The magnetoresistance (MR) properties of antiferromagnetic (AFM) IrMn based giant magnetoresistance-spin valve (GMR-SV) was investigated in view point of the artificial rotation effect of ferromagnetic (FM) layer in the plane induced by an applied field during the post annealing temperature. The MR curves measured with an azimuthal angle region of ${\phi}=0^{\circ}-360^{\circ}$ are depended on the annealing temperature and the magnetization easy axis of two free NiFe layers and two pinned NiFe layers in dual-type GMR-SV film. Especially, the annealing temperature and sample rotation angle(${\theta}$ ) maintained to the magnetic sensitivity (MS) of 1.4 %/Oe with an isotropic region angle of $110^{\circ}$ are $100^{\circ}C$ and $90^{\circ}$, respectively.

• Journal of Ceramic Processing Research
• /
• v.22 no.1
• /
• pp.86-90
• /
• 2021

Fabrication of infrared (IR) transparent ZnS ceramics by spark plasma sintering (SPS) suffers from carbon contamination due to the graphite mold in the SPS system. In the present work, we consolidated transparent ZnS ceramics by SPS using Mo metal foil to prevent the generation of carbonate and/or carbon impurities in the sintered product. The effect of Mo foil on carbon contamination and IR transmittance was investigated. The Fourier transform infrared spectroscopy (FTIR) results revealed that the C-O absorption peak was significantly reduced, however, sulfur vacancies were generated, thus, deteriorating the overall transmittance. The sulfur vacancies were eliminated by post-annealing the specimen in a nitrogen atmosphere, whereby the overall IR transmittance was partially recovered. The results indicate that metal foil wrapping of green bodies could be potentially applicable for the fabrication of carbon contamination-free ZnS ceramics via SPS system.