• Journal of the Korean Ceramic Society
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• v.30 no.3
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• pp.206-214
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• 1993

Coherent precipitation of Zn3P2 during Zn diffusion in a GaInAsP/InP heterostructure was studied using high-resolution transmission electron microscopy. Zn-diffusion-induced intermixing of Ga and In across the GaInAsP/InP heterointerface provided a Ga-mixed InP region which was nearly lattice-matched with Zn3P2 crystal and thus allowed thecoherent precipitation of Zn3P2. The Zn3P2 precipitates were preferentially nucleated at stacking faults which were formed to relax interfacial strain built up by the intermixing. The precipitates were grown to planar epitaxial layer along (100) plane in the lattice-matched region. The TEM images and diffraction pettern revealed that the tetragonal Zn3P2 crystals were coherently matched to the fcc structured GaInP matrix by the {{{{ SQRT {2} $\times$ SQRT {2} $\times$2 }} arrangement. The precipitation reaction of Zn3P2 was explained by an atomic migration model based on the kick-out mechanism.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.439-442
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• 2001

Chalcogenide glassy semiconductors(CGS) can be obtained by the melt quenching technique. We have investigated the thin film heterostructures : metal-chalcogenide glassy semiconductors, where metal is copper, and chalcogenide glassy semiconductors are glasses of the system As-Se. CU/CGS film heterostructure were produced in the vacuum evaporator by the method of vacuum thermal evaporation. Doped films are very sensitive to external actions, and this property allows developing supersensitive precision sensors of temperature, humidity, illumination, and etc. based on them. Cu/CGS film has shown that resistance strongly depend on the temperature. The ratio of resistance vs. temperature has shown over a 2 k$\Omega$/degree. The slop of temperature and resistance shows linear.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.727-730
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• 2002

Chalcogenide glassy semiconductors(CGS) can be obtained by the melt quenching technique. We have investigated the thin film heterostructures : metal-chalcogenide glassy semiconductors, where metal is copper, and chalcogenide glassy semiconductors are glasses of the system As-Se. Cu/CGS film heterostructure were produced in the vacuum evaporator by the method of vacuum thermal evaporation. Doped films are very sensitive to external actions, and this property allows developing supersensitive precision sensors of temperature, humidity, illumination, and etc. based on them. Cu/CGS film has shown that resistance strongly depend on the temperature. The slop of temperature and resistance shows linear.

• Journal of IKEEE
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• v.17 no.4
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• pp.531-536
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• 2013

The impact of UV irradiation process on the AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistor was investigated. Due to the high intensity UV irradiation before the gate dielectric deposition, the conductivity of AlGaN/GaN structure and the drain saturation current of the transistor increased by about 10 %. However, the pinch off characteristics of transistor was severely deformed by the process. By comparing the electrical characteristics of the transistors, it was proposed that the high intensity UV irradiation formed a sub-channel under the two dimensional electron gas of AlGaN/GaN structure even without additional impurity injection.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.4
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• pp.72-75
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• 1985

1.3$\mu$m double-heterostructure GaInAsP/InP wafers have been grown by LPE and broad contact laser diodes have been fabricated. Electrical and optical characteristics of these lasers under pulsed lasing operation at room temperature are described. Typical threshold currents are below 2 Amp. corresponding to threshold current densities of 3 - 6 KAmp./$\textrm{cm}^2$ and peak lasing wavelength is shown to be at 1.315 $\mu$m.

• Laser Solutions
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• v.7 no.3
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• pp.47-50
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• 2004

In this research, we investigated the characteristic of $ZnS_{0.24}Se_{0.76}/GaAs$ heterostructure by using photoreflectance sprctroscopy(PR). The oscillations observed above the 1.43 eV range were attributed Franze-Keldysh effect. The interface electric filed of $GaAs/ZnS_{0.24}Se_{0.76}\;is\;2.153{\times}104\;V/cm$.

• 한국초전도학회:학술대회논문집
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• 2007.07a
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• pp.41-41
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• 2007

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.1
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• pp.39-43
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• 2005

We proposed a structure for a 1.55 ㎛ strained separate confinement heterostructure (SCH) multi- quantum well (MQW) superluminescent diode (SLD), having a tapered active region. SLD was fabricated through a two-step procedure: the first step being metal organic chemical vapor deposition (MOCVD) and the second-step being liquid phase epitaxy (LPE). We used a 15 laterally tilted stripe and window region to suppress the lasing action of the SLD. The performance of the SLD showed output power of 11 mW with no lasing under 200 mA pulse driving. The full-width at half-maximum was 42 nm at 200 mA, 25℃.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.5
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• pp.214-216
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• 2005

Photoreflectance (PR) has been measured to investigate the characterization of the $Al_{0.20}Ga_{0.80}As$/GaAs heterostructures. In the PR spectrum, the 'C' peak is confirmed as the carbon defect with residual impurity originating from the growth process. After annealing, binding energy is relatively weak with As evaporation being done to increase Ga. Also obtained is the electric field value according to annealing temperature ($300{\sim}800^{\circ}C$).

• Journal of the Semiconductor & Display Technology
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• v.10 no.4
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• pp.107-112
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• 2011

This paper is for improving the RF frequency performance of a fabricated 100nm ${\Gamma}$-gate MHEMT, scaling down vertically for the epitaxy-structure layers of the device. Hydrodynamic simulation parameters are calibrated for the fabricated MHEMT with the modulation-doped $In_{0.52}Al_{0.48}As/In_{0.53}Ga_{0.47}$As heterostructure grown on the GaAs substrate. With these calibrated parameters, simulations for the vertically-scaled epitaxial layers of the device are performed and analyzed for DC/RF characteristics, including the quantization effect due to the thickness reduction of InGaAs channel layer. A newly designed epitaxy-structure device shows higher extrinsic transconductance, $g_m$ of 1.556 S/mm, and higher frequency performance, $f_T$ of 222.5 GHz and $f_{max}$ of 849.6 GHz.