Fabrication and Characterization of 4H-SiC MOSFET with MOCVD-Grown Al2O3 Gate Insulator

2007 ◽  
Vol 556-557 ◽  
pp. 787-790 ◽  
Author(s):  
Shiro Hino ◽  
Tomohiro Hatayama ◽  
Naruhisa Miura ◽  
Tatsuo Oomori ◽  
Eisuke Tokumitsu
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chemical Vapor ◽  
Drain Current ◽  
Interface State ◽  
State Density ◽  
Gate Insulator ◽  
Organic Chemical ◽  
Mos Capacitors ◽  
Significant Difference ◽  
Metal Organic

We have fabricated and characterized MOS capacitors and lateral MOSFETs using Al2O3 as a gate insulator. Al2O3 films were deposited by metal-organic chemical vapor deposition (MOCVD) at temperatures as low as 190 oC using tri-ethyl-aluminum and H2O as precursors. We first demonstrate from the capacitance – voltage (C-V) measurements that the Al2O3/SiC interface has lower interface state density than the thermally-grown SiO2/SiC interface. No significant difference was observed between X-ray photoelectron spectroscopy (XPS) Si 2p spectrum from the Al2O3/SiC interface and that from the SiC substrate, which means the SiC substrate was not oxidized during the Al2O3 deposition. Next, we show that the fabricated lateral SiC-MOSFETs with Al2O3 gate insulator have good drain current – drain voltage (ID-VD) and drain current – gate voltage (ID-VG) characteristics with normally-off behavior. The obtained peak values of field-effect mobility (μFE) are between 68 and 88 cm2/Vs.

Oxygen Pressure Controlled Oxidation for Gate Insulator Process of SiC MOSFETs

2018 ◽  
Vol 924 ◽  
pp. 453-456
Author(s):  
Keisuke Kobayashi ◽  
Haruka Shimizu ◽  
Akio Shima
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxidation Process ◽  
Defect Density ◽  
Drain Current ◽  
Interface State ◽  
State Density ◽  
Gate Insulator ◽  
Excess Carbon ◽  
Interface Defect ◽  
Pressure Controlled

For the improvement of a SiC/SiO2 interface of SiC-MOSFET, we examined O2 partial pressure (PO2) controlled (OPC) oxidation process for the gate oxide formation. The OPC oxidation process has a potential to reduce interface state density (Dit) at SiC/SiO2 interface by using appropriate PO2 and oxidation temperature. However the process requires rapid thermal annealing which is not suitable for mass production. Thus we investigated the process using furnace. First, we optimized the OPC oxidation process for the furnace to realize low interface defect density. Secondly, we confirmed that reduction of Dit was determined by desorption of excess carbon in OPC process by the C–ψs measurement and X-ray photoelectron spectroscopy. Finally, a DMOSFET was fabricated using optimized OPC process. We measured the transfer characteristics, and found that the drain current with OPC was larger than without OPC process.

Heteroepitaxial Growth of A1203 Thin Films on Si By Lpcvd

1988 ◽  
Vol 116 ◽  
Author(s):  
M. Ishida ◽  
I. Katakabe ◽  
N. Ohtake ◽  
T. Nakamura
Keyword(s):  
Thin Films ◽  
Chemical Vapor ◽  
Interface State ◽  
State Density ◽  
Gate Insulator ◽  
Heteroepitaxial Growth ◽  
Mos Capacitors ◽  
Pressure Chemical ◽  
Relationship Of ◽  
Substrate Temperatures

AbstractHeteroepitaxial A1203 thin films were grown successfully on Si(lO0) substrates by low—pressure chemical vapor deposition (LP—CVD). The growth was performed at a pressure of 30 Torr by pyrolysis of N2 bubbled AI(CH3)3 and N20 at substrate temperatures above 1000ºC.RHEED patterns indicated that the grown films were ɤ—Al203 single crystals with an orientation relationship of ɤ—Al203(l00)//Si(l00). The ɤ—A1203 films were stable and did not show phase transition after a 1140ºC heat—treatment for 2hr. MOS capacitors with 500—Å—thick A1203 films as a gate insulator showed highfrequency capacitance—voltage (C—V) curves without hysteresis. The A1203 interface state density determined from quasi—static C—V measurements was 1.7 X 1011cm-2eV-1. It can be seen that ɤ—Al203 film is a promising new insulator for Si on Insulator (SOI) structures.

Investigation of the off-current in amorphous silicon thin film transistors for SiO2 and SiNx. gate insulators

1996 ◽  
Vol 424 ◽  
Author(s):  
Jeong Hyun Kim ◽  
Woong Sik Choi ◽  
Chan Hee Hong ◽  
Hoe Sup Soh
Keyword(s):  
Thin Film ◽  
Amorphous Silicon ◽  
Thin Film Transistors ◽  
Chemical Vapor ◽  
Interface State ◽  
State Density ◽  
Gate Insulator ◽  
Defect States ◽  
Silicon Thin Film ◽  
Pressure Chemical

AbstractThe off current behavior of hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFTs) with an atmospheric pressure chemical vapor deposition (APCVD) silicon dioxide (SiO2) gate insulator were investigated at negative gate voltages. The a-Si:H TFT with SiO2 gate insulator has small off currents and large activation energy (Ea) of the off current compared to the a-Si:H TFT with SiNx gate insulator. The holes induced in the channel by negative gate voltage seem to be trapped in the defect states near the a-Si:H/SiO2 interface. The interface state density in the lower half of the band gap of a-Si:H/SiO2 appears to be much higher than that for a-Si:H/SiNx.

scholarly journals Microstrip Array Ring FETs with 2D p-Ga2O3 Channels Grown by MOCVD

Photonics ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 578
Author(s):  
Manijeh Razeghi ◽  
Junhee Lee ◽  
Lakshay Gautam ◽  
Jean-Pierre Leburton ◽  
Ferechteh H. Teherani ◽  
...  
Keyword(s):  
Field Effect Transistors ◽  
Chemical Vapor ◽  
Drain Current ◽  
Significant Advance ◽  
Growth Time ◽  
Organic Chemical ◽  
Transmission Electron ◽  
Metal Organic ◽  
P Type ◽  
Type Conduction

Gallium oxide (Ga2O3) thin films of various thicknesses were grown on sapphire (0001) substrates by metal organic chemical vapor deposition (MOCVD) using trimethylgallium (TMGa), high purity deionized water, and silane (SiH4) as gallium, oxygen, and silicon precursors, respectively. N2 was used as carrier gas. Hall measurements revealed that films grown with a lower VI/III ratio had a dominant p-type conduction with room temperature mobilities up to 7 cm2/Vs and carrier concentrations up to ~1020 cm−3 for thinner layers. High resolution transmission electron microscopy suggested that the layers were mainly κ phase. Microstrip field-effect transistors (FETs) were fabricated using 2D p-type Ga2O3:Si, channels. They achieved a maximum drain current of 2.19 mA and an on/off ratio as high as ~108. A phenomenological model for the p-type conduction was also presented. As the first demonstration of a p-type Ga2O3, this work represents a significant advance which is state of the art, which would allow the fabrication of p-n junction based devices which could be smaller/thinner and bring both cost (more devices/wafer and less growth time) and operating speed (due to miniaturization) advantages. Moreover, the first scaling down to 2D device channels opens the prospect of faster devices and improved heat evacuation.

Electrical and Optical Characteristics of Two-Dimensional MoS2 Film Grown by Metal-Organic Chemical Vapor Deposition

2020 ◽  
Vol 20 (6) ◽  
pp. 3563-3567 ◽  
Author(s):  
Donghwan Kim ◽  
Yonghee Jo ◽  
Dae Hyun Jung ◽  
Jae Suk Lee ◽  
TaeWan Kim
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Layer Structure ◽  
Chemical Vapor ◽  
Atomic Layer ◽  
Surface Element ◽  
Organic Chemical ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

Atomically thin molybdenum disulfide (MoS2) films were synthesized on a SiO2/Si substrate by metal-organic chemical vapor deposition (MOCVD). Raman spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy studies reveal the double-atomic-layer structure and the surface element composition of the MOCVD-grown MoS2 films. The photoluminescence measurement demonstrates a strong emission peak with a bandgap of 685.1 nm, attributed to highly efficient radiative transition at the double atomic layer. The contact resistance between the doubleatomic-layer MoS2 film and metal electrode was measured using the transmission-line modeling method. A Ti/Au electrode forms an ohmic contact with the double-atomic-layer MOCVD-grown MoS2 film, exhibiting a resistivity of 100 kΩ. The field-effect transistor based on the double-atomiclayer MoS2 film exhibits an electron mobility of 1.3×10−4 cm2/V·s and an on/off ratio of 6.5×102 at room temperature.

scholarly journals Fabrication and Characterization of GaN Junctionfield Effect Transistors

2000 ◽  
Vol 5 (S1) ◽  
pp. 376-383
Author(s):  
L. Zhang ◽  
L. F. Lester ◽  
A. G. Baca ◽  
R. J. Shul ◽  
P. C. Chang ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Field Effect Transistors ◽  
Chemical Vapor ◽  
Drain Current ◽  
Organic Chemical ◽  
Microwave Measurement ◽  
Theoretical Predictions ◽  
Metal Organic ◽  
Current Reduction ◽  
Increasing Temperature

Junction field effect transistors (JFET) were fabricated on a GaN epitaxial structure grown by metal organic chemical vapor deposition. The DC and microwave characteristics, as well as the high temperature performance of the devices were studied. These devices exhibited excellent pinch-off and a breakdown voltage that agreed with theoretical predictions. An extrinsic transconductance (gm) of 48 mS/mm was obtained with a maximum drain current (ID) of 270 mA/mm. The microwave measurement showed an fT of 6 GHz and an fmax of 12 GHz. Both the ID and the gm were found to decrease with increasing temperature, possibly due to lower electron mobility at elevated temperatures. These JFETs exhibited a significant current reduction after a high drain bias was applied, which was attributed to a partially depleted channel caused by trapped electrons in the semi-insulating GaN buffer layer.

Growth and Physical Properties of MOCVD-Deposited Hafnium Oxide Films and Their Properties on Silicon

2002 ◽  
Vol 745 ◽  
Author(s):  
S. Van Elshocht ◽  
M. Caymax ◽  
S. De Gendt ◽  
T. Conard ◽  
J. Pétry ◽  
...  
Keyword(s):  
Physical Properties ◽  
Hafnium Oxide ◽  
Deposition Temperature ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Oxide Thickness ◽  
State Density ◽  
Organic Chemical ◽  
Organic Contamination ◽  
Metal Organic

ABSTRACTThis paper discusses metal organic chemical vapor deposited (MOCVD) HfO2 layers using tetrakis(diethylamido)hafnium (TDEAH) as precursor. We have studied the influence of the starting surface and deposition temperature on the growth kinetics and physical properties of the HfO2 layers. Important characteristics such as crystalline state, density, and organic contamination in the layers were found to be dependent on these parameters.Typical for this deposition process is the formation of an interfacial layer underneath the high-k layer. Its composition and thickness, affecting scaling of the equivalent oxide thickness, are shown to be closely related to the HfO2 process parameters mentioned above.Finally, we will show electrical results for HfO2/polySi gate stacks indicating the effect for deposition temperature.

Investigation of Interface State Density with Varied SiO2 Thickness in La2O3/SiO2/4H-SiC MOS Capacitors

2016 ◽  
Vol 858 ◽  
pp. 689-692 ◽  
Author(s):  
Yu Cheng Wang ◽  
Yu Ming Zhang ◽  
Ren Xu Jia
Keyword(s):  
Photoelectron Spectroscopy ◽  
Lattice Mismatch ◽  
Atomic Layer ◽  
Interface State ◽  
Carbon Cluster ◽  
State Density ◽  
Oxide Semiconductor ◽  
Interface Quality ◽  
Mos Capacitors ◽  
Layer Deposition

SiO2 with varying thickness (0, 4.45, and 8.05 nm) were grown on n type 4H-SiC epilayer by thermal oxidation and La2O3 were stacked on them using atomic layer deposition (ALD). The La2O3/SiO2/4H-SiC metal-oxide-semiconductor (MOS) capacitors were analyzed by X-ray photoelectron spectroscopy (XPS) and capacitance-voltage (C-V) measurements. C-V curves show that introducing an ultrathin SiO2 can reduce the effect of lattice mismatch of La2O3/4H-SiC structure and then improve interface property. However, the interface quality is reduced as SiO2 was grown thicker. XPS data show that more carbon cluster remains at the interfacial between SiO2 and 4H-SiC as the oxidation time increases.

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