김성근 교수

TiO 2 thin films with high dielectric constants (83–100) were grown on a Ru electrode at a growth temperature of 250 °C using the atomic-layer deposition method. The as-deposited films were crystallized with rutile structure. Adoption of O3 with a very high concentration (400g∕m3) was crucial for obtaining the rutile phase and the high dielectric constant. The leakage current density of a TiO2 film with an equivalent oxide thickness of 1.0–1.5 nm was 10−6–10−8A∕cm2 at ±1V. All these electrical p

Al-doped TiO2 thin films to be used in future DRAM capacitors with excellent leakage properties as well as high dielectric constants are fabricated. The next generation stack structured DRAM cell composed of a transistor and a capacitor is shown (see Figure). A large cell capacitance is required for successful operation of DRAMs irrespective of the feature size of the cell. Therefore, as scaling down of the DRAMs proceeds, a higher-k material such as Al-doped TiO2 has to be eventually implemente

Abstract The recent progress in the metal‐insulator‐metal (MIM) capacitor technology is reviewed in terms of the materials and processes mostly for dynamic random access memory (DRAM) applications. As TiN/ZrO 2 ‐Al 2 O 3 ‐ZrO 2 /TiN (ZAZ) type DRAM capacitors approach their technical limits, there has been renewed interest in the perovskite SrTiO 3 , which has a dielectric constant of >100, even at a thickness ∼10 nm. However, there are many technical challenges to overcome before this type o

films were deposited by atomic layer deposition (ALD) using trimethylaluminum and as precursor and oxidant, respectively, at growth temperatures ranging from room temperature to on Si(100) substrates. Growth rate and refractive index of the films decreased from and increased from 1.52 to 1.65, respectively, with increasing growth temperature. The dielectric constant slightly increased from 6.8 to 8 with increasing growth temperature in the same temperature range. films grown using as oxidant sho

Grafting nanotechnology on thermoelectric materials leads to significant advances in their performance. Creation of structural defects including nano-inclusion and interfaces via nanostructuring achieves higher thermoelectric efficiencies. However, it is still challenging to optimize the nanostructure via conventional fabrication techniques. The thermal instability of nanostructures remains an issue in the reproducibility of fabrication processes and long-term stability during operation. This wo

Ru thin films were grown on Si, , , and TiN substrates by atomic-layer deposition using 2,4-(dimethylpentadienyl)(ethylcyclopentadienyl)Ru and as Ru precursor and reactant, respectively, at temperatures ranging from . A saturated growth rate of and a low oxygen concentration (below the detection limit of Auger electron spectroscopy) were obtained at . The Ru film showed a negligible incubation period on all the different types of substrates, and an active nucleation behavior which resulted in a

Ru thin films were grown on Au, Pt, TiN, TiO2, and SiO2 substrates by atomic layer deposition using 2,4-(dimethylpentadienyl)(ethylcyclopentadienyl)Ru (DER) dissolved in ethylcyclohexane at a concentration of 0.2 M as the Ru precursor and O2 as the reactant. There was a long incubation time for Ru film deposition on TiN and SiO2 due to the weak interaction between DER and the covalent bonds in TiN and SiO2. On the other hand, the Ru films on TiO2 exhibited a shorter incubation time. There was a

A new deposition technique is required to grow the active oxide semiconductor layer for emerging oxide electronics beyond the conventional sputtering technique. Atomic layer deposition (ALD) has the benefits of versatile composition control, low defect density in films, and conformal growth over a complex structure, which can hardly be obtained with sputtering. This study demonstrates the feasibility of growing amorphous In-Zn-Sn-O (a-IZTO) through ALD for oxide thin-film transistor (TFT) applic

This study examined the effect of Al incorporation on the growth behavior of TiO2 thin films deposited by atomic layer deposition (ALD) using Al(CH3)3, and Ti(O-i-C3H7)4 as the precursors and O3 as the reactant. Al-doped TiO2 thin films were deposited at a growth temperature of 250 °C, which was within the ALD window for both precursors. Despite the discrete feeding of the Al precursor, Al ions easily diffused along the direction normal to the film surface forming a uniform Al-doped thin film, e

thin films were grown on substrates by atomic layer deposition. A high dielectric constant was obtained due to the formation of a high-temperature crystalline form, tetragonal or cubic. The origin of the formation of the high-temperature form was examined by depositing films on two types of surfaces, anatase and rutile. Tetragonal or cubic films were formed on both substrates. This suggests that growth-controlled selection is responsible for the formation of the metastable phase , not the minimi

High performance single-walled carbon nanotube field effect transistors (SWCNT-FETs) fabricated with thin atomic layer deposited (ALD) Al2O3 as gate dielectrics and passivation layer are demonstrated. A 1.5μm gate-length SWCNT-FETs with 15nm thick Al2O3 insulator shows a gate leakage current below 10−11A at −2.5V<Vg<+7V, a subthreshold swing of S∼105mV∕decade, and a maximum on current of −12μA at a reverse gate bias of −1V. Lack of hysteresis in IV characteristics and low low frequ