- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Self-assembly of a lateral quasi-Ohmic CuInSe <sub/>2</sub> /InSe isotype heterojunction for flexible devices by pulsed laser deposition
摘要: The contacts between two-dimensional InSe films and metal electrodes play an important role in nanoelectronics flexible devices. Generally, there is a large work function difference between the Au and InSe films, which would form a Schottky contact to deteriorate device performances. Herein, we designed a lateral self-assembled CuInSe2/InSe isotype heterojunction on a flexible mica substrate by pulsed laser deposition, which could improve the contact performances between electrodes and InSe films. By combining the X-ray photoelectron spectroscopy and Kelvin probe force microscopy results, the In rich CuInSe2 and InSe regions could act as quasi-n+-n junctions for reduction of the contact resistance with electrodes. Compared to the InSe films with Au electrodes, the CuInSe2/InSe isotype heterojunction presents approximately half channel resistance and four times photocurrent values. Moreover, the heterojunction devices can still maintain relatively good performance under bending states by restraining the dark current. The present work proves the potential of CuInSe2/InSe isotype heterojunctions for flexible applications.
关键词: pulsed laser deposition,flexible devices,isotype heterojunction,CuInSe2/InSe,quasi-Ohmic contact
更新于2025-09-19 17:13:59
-
Metal-insulator-semiconductor structure for deep-ultraviolet light-emitting diodes to increase the electron injection in the cathode region
摘要: In this work, we propose using metal-insulator-semiconductor (MIS) structure on the n-AlGaN layer to reduce the contact resistance and improve the wall-plug efficiency (WPE) for AlGaN based deep ultraviolet light-emitting diodes (DUV LEDs). The thin insulator between the cathode metal and the n-AlGaN layer can share the bias, which makes the n-AlGaN layer surface less depleted and thus the MIS-type cathode structure favors the intraband tunneling effect for electrons. Moreover, the adoption of the MIS-structure aligns the electron affinity for the metal above the conduction band for the n-AlGaN layer, and this avoids the electron transport by thermionic emission. Thanks to the MIS-type cathode, we find that excellent electron transport can be obtained even if the metal with big electron affinity is used. This work also conducts an in-depth investigation into the impact of the relative dielectric constant, the bandgap, the affinity, the length and the thickness for the insulator on the electron transport and the WPE of DUV LEDs. We find that an insulator with a small dielectric constant is required for promoting the electron tunneling in the MIS-type cathode region.
关键词: Insulator,DUV LEDs,Ohmic contact,n-AlGaN,MIS structure
更新于2025-09-19 17:13:59
-
Laser Annealing Simulations of Metallisations Deposited on 4H-SiC
摘要: Based on the finite elements method, thermal simulations were conducted to reproduce a laser annealing of several metals deposited on 4H-SiC. We estimated the temperature reached at the metal/4H-SiC interface to find out the best conditions to achieve ohmic contact formation through laser annealing. An optimization of Al/Ti/4H-SiC stacking was also considered. Simulations highlighted the low temperature of the non-irradiated SiC face that allows using grinded wafer.
关键词: 4H-SiC,Laser annealing,Simulation,Ohmic contact
更新于2025-09-16 10:30:52
-
GaSe/MoS <sub/>2</sub> Heterostructure with Ohmica??Contact Electrodes for Fast, Broadband Photoresponse, and Selfa??Driven Photodetectors
摘要: In this letter, the vertically-stacked GaSe/MoS2 heterostructures with indium tin oxide (ITO) and Ni/Au as contact electrodes are successfully fabricated, respectively. The GaSe/MoS2 heterostructure exhibits a broadband photoresponse covering the range of visible to near-infrared spectra at room temperature without external bias voltage. When ITO serves as contact electrodes, a high rectification ratio, i.e., 1.5 × 104 at VDS = ±1 V, and an excellent photoelectric performance, i.e., responsivity of ≈0.67 A W-1, specific detectivity of ≈2.3 × 1011 cm Hz1/2 W-1 and external quantum efficiency of ≈160% at the wavelength of 520 nm is achieved. Moreover, the GaSe/MoS2 heterostructure with Ohmic-contact ITO electrodes demonstrates a faster response time of 155 μs, which is 4 times faster than the GaSe/MoS2 heterostructure with Ni/Au electrodes and about 300 times faster than previous reports. These results reveal the presence of an abrupt p–n junction between GaSe and MoS2 and significant role of electrode-contact mode in determining the photoelectric properties of GaSe/MoS2 heterostructure.
关键词: photoresponse,GaSe/MoS2 heterostructure,self-driven photodetector,Ohmic-contact
更新于2025-09-16 10:30:52
-
Ternary Ti–Si–C alloy film formation on GaN and contact properties
摘要: Ternary Ti–Si–C alloy films were deposited on GaN substrates (n-type and p-type) by the radio- frequency magnetron sputtering method. The electrical properties of contact films with various chemical compositions were investigated. The microstructures were examined by X-ray diffractometry and transmission electron microscopy. The electrical properties of the contact films were improved after annealing at 873 K for 60 s. Ohmic contact characteristics were obtained for n-type GaN. The TiN phase plays an important role in obtaining the ohmic contact. The effect of deposition and annealing on the electrical properties between Ti–Si–C film and GaN are discussed based on the experimental results.
关键词: Compound semiconductors,Contact properties,GaN,Ohmic contact,Thin film
更新于2025-09-10 09:29:36
-
[IEEE 2018 IEEE International Conference on Electron Devices and Solid State Circuits (EDSSC) - Shenzhen (2018.6.6-2018.6.8)] 2018 IEEE International Conference on Electron Devices and Solid State Circuits (EDSSC) - Carrier Injection Mechanism of Metal-MoS<inf>2</inf> Ohmic Contact in MoS<inf>2</inf> FETs
摘要: In order to enhance the carrier injection of MoS2 field effect transistors (FETs,) understanding the injection mechanism of metal-MoS2 contacts is essential. In this work, MoS2 (FETs) with Ti and Sc electrodes were fabricated and characterized, respectively. The carrier injection mechanism was studied from the perspective of the tunneling models. With the narrower barrier width, the Sc-MoS2 contact shows a different injection mechanism from that of Ti-MoS2, making Sc a promising improvement as MoS2 FETs electrodes.
关键词: Ohmic contact,MoS2,tunneling,field effect transistor (FET)
更新于2025-09-09 09:28:46
-
Gallium Oxide || Ga2O3-based gas sensors
摘要: β-Ga2O3 has recently gained a lot of interest for applications in solar-blind deep ultraviolet (UV) detectors and high-power electronics at elevated temperatures. The interest stems from its intrinsic material properties, such as wide-bandgap nature (4.9 eV) and high breakdown electric field. β-Ga2O3 can also serve as a reactive oxide layer, sensitive to a wide variety of gases, especially at high temperatures in harsh environments. Many β-Ga2O3-based gas sensors have been reported recently [1–20]. In this chapter, the gas sensing mechanism and the sensing characteristics of β-Ga2O3 are reviewed. First, the material properties of β-Ga2O3 are reviewed for a clear understanding of surface reactions at oxide surfaces with various gas molecules. The crystal structure of β-Ga2O3 and the surface atomic configurations of 201 and (010)-oriented β-Ga2O3 are investigated. The wet and dry etching characteristics and the metal contact properties of 201 and (010) β-Ga2O3 single crystals are discussed for a broad range of device applications. Recent reports of β-Ga2O3-based hydrogen sensors are discussed, and the hydrogen sensing properties of 201 and (010) β-Ga2O3 single crystals are compared for enhanced hydrogen detection.
关键词: crystal structure,β-Ga2O3,high-temperature applications,wet and dry etching,Ohmic contact,gas sensors,hydrogen sensors
更新于2025-09-09 09:28:46