• Transactions of the Korean Society of Automotive Engineers
• /
• v.25 no.2
• /
• pp.149-156
• /
• 2017

Various kinds of accessories(e.g., clock, radio, automatic door locks, alarm devices, etc.) or unit components (e.g., black box, navigation system, alarm, private audio, etc.) require dark current even when the vehicle power is turned off. However, accessories or unit components can be the causes of excessive dark current generation. It results in battery discharge and the vehicle's failure to start. Therefore, immediate detection of abnormal dark current and response are very important for a successful repair job. In this paper, we can increase the maintenance efficiency by presenting a standardized diagnostic process for the measurement of the dark current and the existing problem. As a result of the absence of a system to block the dark current in a vehicle, diagnosis and repair were performed immediately by using a standardized dark current diagnostic process.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.15 no.2
• /
• pp.232-242
• /
• 2015

Analytical study of surface recombination at the $Si/SiO_2$ interface is carried out in order to set the optimum surface conditions that result in minimum dark base current and maximum open circuit voltage in silicon solar cells. Recombination centers are assumed to form a continuum rather than to be at a single energy level in the energy gap. It is shown that the presence of a hump in the dark I-V characteristics of high efficiency PERL cells is due to the dark current transition from a high surface recombination regime at low voltage to a low surface recombination regime at high voltage. Successful fitting of reported dark I-V characteristics of a typical PERL cell is obtained with several possible combinations of surface parameters including equal electron and hole capture cross sections.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.07b
• /
• pp.961-964
• /
• 2003

This paper presents the temperature annealing effect on the dark current of the InGaAs waveguide photodiodes, which are developed for high-speed optical receivers. The interesting experimental phenomena were observed that the dark current is significantly decreased and the breakdown voltage is slightly increased after annealing at $250^{\circ}C$ whereas the dark current and the breakdown voltage are almost constant after annealing at $200^{\circ}C$. Based on the experimental results, the long-term annealing is more effective for the dark current improvement than the conventional curing process.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.5 no.2
• /
• pp.102-106
• /
• 2005

A low dark current CMOS image sensor (CIS) pixel without any process modification is developed. Dark current is mainly generated at the interface region of shallow trench isolation (STI) structure. Proposed pixel reduces the dark current effectively by separating the STI region from the photodiode junction using simple layout modification. Test sensor array that has both proposed and conventional pixels is fabricated using 0.18 m CMOS process and the characteristics of the sensor are measured. The result shows that the dark current of the proposed pixel is 0.93fA/pixel that is two times lower than the conventional design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.05b
• /
• pp.31-34
• /
• 2002

In this paper, the electric properties of amophous selenium multilayer samples has been investigated. In order to develop the hybrid flat-panel digital· X-ray image detector, we measured and analyzed their performance parameters such as the X -ray sensitivity and dark-current for a amophous selenium multilayers X-ray detector with a phosphor layer, The hybrid digital X-ray image detector can be constructed by integrating a phosphor layer (or a scintillative layer) that convert X-ray to a light on a-Se photoconduction mulilayers that convert a light to electrical signal. As results, the dielectric materials such as parylene between the phosphor layer and the top electrode may reduce the dark-current of the samples. Amorphous selenium multilayers having dielectric layer(parylene) has characteristics of low dark-current, high X-ray sensitivity. So we can acquired a enhanced signal to noise ratio. In this paper offer the method can reduce the dark-current in the hybrid X-ray detector.

• The Bulletin of The Korean Astronomical Society
• /
• v.44 no.2
• /
• pp.53.1-53.1
• /
• 2019

The cosmic dark sector, composed of dark energy and dark matter, might be coupled, and hence mediate a fifth-force which gives rise to distinctive cosmological signatures. I will consider an interacting dark sector, in which dark energy and dark matter are coupled via specific well-motivated coupling functions. After an overview of these coupled dark energy models, I will discuss the current model parameter constraints derived from the latest cosmological observations which probe the expansion history, and the growth of cosmic structures of our Universe. Moreover, I will demonstrate how different measurements of the Hubble constant, including the GW170817 measurement, influence the inferred constraints on the dark coupling. I will further discuss how one could put tighter constraints on such a dark sector coupling with the upcoming large-scale radio surveys.

• Proceedings of the IEEK Conference
• /
• 2004.08c
• /
• pp.482-485
• /
• 2004

We fabricated a hybrid bulk/fully depleted silicon on insulator (FDSOI) complementary metal oxide semiconductor (CMOS) active pixel image sensor. The active pixel is comprised of reset and source follower transistors on the SOI seed wafer, while the pinned photodiode and readout gate and floating diffusion are fabricated on the SOI handle wafer after the removal of the buried oxide. The source of dark current is eliminated by hybrid bulk/FDSOI pixel structure between localized oxidation of silicon (LOCOS) and photodiode(PD). By using the low noise hybrid pixel structure, dark currents qm be suppressed significantly. The pinned photodiode can also be optimized for quantum efficiency and reduce the noise of dark current. The spectral response of the pinned photodiode on the SOI handle wafer is very flat between 400 nm and 700 nm and the dark current that is higher than desired is about 10 nA/cm2 at a $V_{DD}$ of 2 V.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.07a
• /
• pp.388-389
• /
• 2005

In this paper, the electric properties of mercury Iodide multi-layer samples has been investigated. We measured and analyzed their performance parameters such as the X-ray sensitivity and dark-current for a mercury Iodide multi-layer X-ray detector with a dielectric layer. The digital X-ray image detector can be constructed by integrating photoconduction multi-layer that dielectric layer has characteristics of low dark-current, high X-ray sensitivity. However this process has found to have complexity on the performance of the sample. We have investigate dielectric layer that it substitute dielectric layer for HgO(Mercury Oxide). We have employed two approaches for producing the mercury Iodide sample : 1) Physical Vapor Deposition(PVD) and 2) Particle-In-Binder(PIB). In this paper fabricated by PIB Method with thicknesses ranging from approximately 180um to 240um and we could produce high-quality samples for each technique particular application. As results, the dielectric materials such as HgO between the dielectric layer and the top electrode may reduce the dark-current of the samples. Mercury Iodide multi-layer having HgO has characteristics of low dark-current, high X-ray sensitivity and simple processing. So we can acquired a enhanced signal to noise ratio. In this paper offer the method can reduce the dark-current in the X-ray detector.

• Nuclear Engineering and Technology
• /
• v.29 no.6
• /
• pp.468-475
• /
• 1997

The transient photocurrent in amorphous silicon radiation detectors (n-i-n and forward biased p-i-n) were analyzed. The transient photocurrents in these devices could be modeled using multiple trap levels in the forbidden gap. Using this model the rise and decay shapes of the photocurrents could be fitted. The decaying photocurrent shapes of the p-i-n and n-i-n devices after a short duration of light pulse showed a similar behavior at low dark current density levels, but at higher dark current density levels the photocurrent of the p-i-n diode decayed faster than that of the n-i-n, which could be explained by the decreased electron lifetimes in the forward biased p-i-n diode at high dark current densities. The transient photoconductive gain behaviors in the amorphous silicon radiation detectors are discussed in terms of device configuration, dark current density and time scale.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.348-348
• /
• 2016

Low dark current (off-current) and high photo current are both essential for a solution processed organic photodetector (OPD) to achieve high photo-responsivity. Currently, most OPDs utilize a bulk heterojunction (BHJ) photo-active layer that is prepared by the one-step deposition of a polymer:fullerene blend solution. However, the BHJ structure is the main cause of the high dark current in solution processed OPDs. It is revealed that the detectivity and spectral responsivity of the OPD can be improved by utilizing a photo-active layer consisting of an interdiffused polymer/fullerene bilayer (ID-BL). This ID-BL is prepared by the sequential solution deposition (SqD) of poly(3-hexylthiophene) (P3HT) and [6,6] phenyl C61 butyric acid methyl ester (PCBM) solutions. The ID-BL OPD is found to prevent undesirable electron injection from the hole collecting electrode to the ID-BL photo-active layer resulting in a reduced dark current in the ID-BL OPD. Based on dark current and external quantum efficiency (EQE) analysis, the detectivity of the ID-BL OPD is determined to be $7.60{\times}1011$ Jones at 620 nm. This value is 3.4 times higher than that of BHJ OPDs. Furthermore, compared to BHJ OPDs, the ID-BL OPD exhibited a more consistent spectral response in the range of 400 - 660 nm.