Strong Visible Photoluminescence in Silicon Nitride thin Films Deposited at High Rates

1993 ◽  
Vol 325 ◽  
Author(s):  
Sadanand V. Deshpande ◽  
Erdogan Gulari ◽  
Steven W. Brown ◽  
S.C. Rand
Keyword(s):  
Thin Films ◽  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Amorphous Materials ◽  
Visible Region ◽  
Chemical Vapor ◽  
Peak Position ◽  
Deposition Rates ◽  
Nitrogen Alloy ◽  
Hot Filament

AbstractAmorphous silicon nitrogen alloy (a-Si:Nx) thin films have been deposited using a novel hot filament chemical vapor deposition (HFCVD) technique. In this method, a hot tungsten filament is used to decompose ammonia to obtain highly reactive nitrogen precursor species which further react with disilane to form silicon nitride thin films. This allows for very high deposition rates ranging from 600 Å/min to 2500 Å/min at low substrate temperatures. These films deposited at high rates show strong photoluminescence (PL) at room temperature in the visible region when excited with the 457 nm line of Ar+ ion laser. Intrinsic defects introduced into the amorphous silicon nitride matrix due to the rapid deposition rates seem to give rise to the visible PL. The PL intensity is at least 8-10 times stronger than silicon nitride films deposited by conventional plasma enhanced CVD. PL peak position of this broad luminescence was varied in the visible region by changing the film stoichiometry (Si/N ratio). The PL peak energy also scales predictably with the refractive index and optical band gap of the films. These samples showed reversible PL fatigue and also have band edge tail states characteristic of amorphous materials.

scholarly journals Effect of Thermal Annealing on the Photoluminescence of Dense Si Nanodots Embedded in Amorphous Silicon Nitride Films

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 354
Author(s):  
Qianqian Liu ◽  
Xiaoxuan Chen ◽  
Hongliang Li ◽  
Yanqing Guo ◽  
Jie Song ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Thermal Annealing ◽  
Chemical Vapor ◽  
Peak Position ◽  
Excitation Wavelength ◽  
Very High Frequency ◽  
Amorphous Silicon Nitride ◽  
Silicon Nitride Films ◽  
High Frequency Plasma

Luminescent amorphous silicon nitride-containing dense Si nanodots were prepared by using very-high-frequency plasma-enhanced chemical vapor deposition at 250 °C. The influence of thermal annealing on photoluminescence (PL) was studied. Compared with the pristine film, thermal annealing at 1000 °C gave rise to a significant enhancement by more than twofold in terms of PL intensity. The PL featured a nanosecond recombination dynamic. The PL peak position was independent of the excitation wavelength and measured temperatures. By combining the Raman spectra and infrared absorption spectra analyses, the enhanced PL was suggested to be from the increased density of radiative centers related to the Si dangling bonds (K0) and N4+ or N20 as a result of bonding configuration reconstruction.

Preparation and Spectrial Studies of Silicon Nitride Thin Films Containing Amorphous Silicon Quantum Dots

2021 ◽  
Vol 323 ◽  
pp. 48-55
Author(s):  
Jia Xin Sun ◽  
Bing Qing Zhou ◽  
Xin Gu
Keyword(s):  
Thin Films ◽  
Quantum Dots ◽  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Raman Spectra ◽  
Annealing Temperature ◽  
Chemical Vapor ◽  
Blue Shift ◽  
Silicon Quantum Dots ◽  
Plasma Chemical Vapor Deposition

Silicon-rich silicon nitride thin films are prepared on P-type monocrystalline silicon wafer (100) and glass substrate by plasma chemical vapor deposition with reaction gas sources SiH4 and NH3. The deposited samples are thermally annealed from 600°C to 1000°C in an atmosphere furnace filled with high purity nitrogen. The annealing time is 60 minutes. Fourier transform infrared spectroscopy (FTIR) is carried out to investigate the bonding configurations in the films. The results show that the Si-H bond and N-H bond decrease with the increase of annealing temperature, and completely disappear at the annealing temperature of 900°C. But the Si-N bond is enhanced with the increase of annealing temperature, and the blue shift occurs, then Si content in the film increases. The Raman Spectra show that the amorphous Si Raman peak appears at 480 cm-1 in the film at 700°C. The Raman spectra of the films annealed at 1000 °C is fitted with two peaks, and a peak at 497 cm -1 is found, which indicated that the Si phase in the films changed from amorphous to crystalline with the increase of annealing temperature. The experiment also analyses the luminescence properties of the samples through PL spectrum, and it is found that there are five luminescence peaks in each sample under different annealing temperature. Based on the analysis of Raman spectrum and FTIR spectrum, the PL peak of amorphous silicon quantum dots appears at the wavelength range of 525-555nm, and the other four PL peaks are all from the defect state luminescence in the thin films, and the amorphous silicon quantum dot size is calculated according to the formula.

Effects of Substrate Temperature on the Properties of Silicon Nitride Films by PECVD

2013 ◽  
Vol 537 ◽  
pp. 12-15
Author(s):  
Chun Ya Li ◽  
Xi Feng Li ◽  
Long Long Chen ◽  
Ji Feng Shi ◽  
Jian Hua Zhang
Keyword(s):  
Thin Films ◽  
Silicon Nitride ◽  
Visible Region ◽  
Chemical Vapor ◽  
Growth Conditions ◽  
Glass Substrates ◽  
Silicon Nitride Films ◽  
Atomic Force ◽  
Average Transmittance ◽  
Surface Morphologies

Under different growth conditions, silicon nitride (SiNx) thin films were deposited successfully on Si(100) substrates and glass substrates by plasma enhanced chemical vapor deposition (PECVD). The thickness, refractive index and growth rate of the thin films were tested by ellipsometer. The surface morphologies of the thin films were investigated using atomic force microscope (AFM). The average transmittance in the visible region was over 90%.

Enhanced crystallization and phase transformation of amorphous silicon nitride under high pressure

2001 ◽  
Vol 16 (1) ◽  
pp. 67-75 ◽  
Author(s):  
Ya-Li Li ◽  
Yong Liang ◽  
Fen Zheng ◽  
Xian-Feng Ma ◽  
Suo-Jing Cui ◽  
...  
Keyword(s):  
High Pressure ◽  
Phase Transformation ◽  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Crystallization Temperature ◽  
Amorphous Materials ◽  
Normal Pressure ◽  
Nucleation And Growth ◽  
Amorphous Silicon Nitride ◽  
Amorphous Si

The crystallization and phase transformation of amorphous Si3N4 ceramics under high pressure (1.0–5.0 GPa) between 800 and 1700 °C were investigated. A greatly enhanced crystallization and α–β transformation of the amorphous Si3N4 ceramics were evident under the high pressure, as characterized by that, at 5.0 GPa, the amorphous Si3N4 began to crystallize at a temperature as low as 1000 °C (to transform to a modification). The subsequent a–b transformation occurred completed between 1350 and 1420 °C after only 20 min of pressing at 5.0 GPa. In contrast, under 0.1 MPa N2, the identical amorphous materials were stable up to 1400 °C without detectable crystallization, and only a small amount of a phase was detected at 1500 °C. The crystallization temperature and the a–b transformation temperatures are reduced by 200–350 °C compared to that at normal pressure. The enhanced phase transformations of the amorphous Si3N4 were discussed on the basis of thermodynamic and kinetic consideration of the effects of pressure on nucleation and growth.

Microbridge Testing of Thin Films Under Small Deformation

1999 ◽  
Vol 594 ◽  
Author(s):  
T. Y. Zhang ◽  
Y. J. Su ◽  
C. F. Qian ◽  
M. H. Zhao ◽  
L. Q. Chen
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Silicon Nitride ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Chemical Vapor ◽  
Small Deformation ◽  
Nitride Film ◽  
Silicon Nitride Film ◽  
Pressure Chemical

AbstractThe present work proposes a novel microbridge testing method to simultaneously evaluate the Young's modulus, residual stress of thin films under small deformation. Theoretic analysis and finite element calculation are conducted on microbridge deformation to provide a closed formula of deflection versus load, considering both substrate deformation and residual stress in the film. Silicon nitride films fabricated by low pressure chemical vapor deposition on silicon substrates are tested to demonstrate the proposed method. The results show that the Young's modulus and residual stress for the annealed silicon nitride film are respectively 202 GPa and 334.9 MPa.

Hydrogen Release and Si-N Bond-Healing Infrared Study of Rapid Thermal Annealed Amorphous Silicon Nitride Thin Films

1995 ◽  
Vol 398 ◽  
Author(s):  
P. Santos-Filho ◽  
G. Stevens ◽  
Z. Lu ◽  
K. Koh ◽  
G. Lucovsky
Keyword(s):  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Gas Flow ◽  
Structural Changes ◽  
Thermal Dissociation ◽  
Chemical Vapor ◽  
Hydrogen Release ◽  
Ex Situ ◽  
Infrared Study ◽  
Amorphous Silicon Nitride

ABSTRACTWe address aspects of hydrogen bonding and its thermal evolution in amorphous Silicon nitride films grown by Remote Plasma Enhanced Chemical Vapor Deposition (RPECVD) from SiH4 and NH3 (or ND3) source gases. Rapid Thermal Annealing (RTA) decreases the Si-H(D) and SiN-H(D) bond populations. The hydrogen bonds break, and H2 (HD, D2) forms and evolves from the film with the heat treatment. This molecular hydrogen release is accompanied by Si- and N- bond healing as detected by a SiN infra red stretch mode signal gain. The ex-situ RTA experiment temperatures ranged from 400 °C to 1200 °C, in 100 °C steps and the film structural changes were monitored by Fourier Transform Infrared spectroscopy (FTIR) after each incremental anneal. Gas flow ratios R=NH3/SiH4 > 2 produced films in which SiN-H(D) bonds dissociated, and a gas desorption rate equation estimated an activation energy barrier of Ea = 0.3 eV. The release of hydrogen from the films in the form of H2 (D2) and ammonia radicals was detected by mass spectrometry and is shown here. The re-bonding of nitrogen to silicon upon thermal dissociation of hydrogen's is consistent with the improvement of the electrical properties of a-SiN:H films following RTA treatment.

Effect of Nitrogen Doping on the Structure and Optical Properties of N-Type Hydrogenated Amorphous Silicon Thin Films

2011 ◽  
Vol 383-390 ◽  
pp. 6980-6985
Author(s):  
Mao Yang Wu ◽  
Wei Li ◽  
Jun Wei Fu ◽  
Yi Jiao Qiu ◽  
Ya Dong Jiang
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Amorphous Silicon ◽  
Photoelectron Spectroscopy ◽  
Gas Flow ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapor ◽  
Silicon Thin Films ◽  
Frequency Plasma ◽  
Hydrogenated Amorphous

Hydrogenated amorphous silicon (a-Si:H) thin films doped with both Phosphor and Nitrogen are deposited by ratio frequency plasma enhanced chemical vapor deposition (PECVD). The effect of gas flow rate of ammonia (FrNH3) on the composition, microstructure and optical properties of the films has been investigated by X-ray photoelectron spectroscopy, Raman spectroscopy and ellipsometric spectra, respectively. The results show that with the increase of FrNH3, Si-N bonds appear while the short-range order deteriorate in the films. Besides, the optical properties of N-doped n-type a-Si:H thin films can be easily controlled in a PECVD system.

Measurement of The Activation Energy in Phosphorous Doped Polycrystalline Diamond Thin Films Grown on Silicon Substrates by Hot Filament Chemical Vapor Deposition

1996 ◽  
Vol 423 ◽  
Author(s):  
S. Mirzakuchaki ◽  
H. Golestanian ◽  
E. J. Charlson ◽  
T. Stacy
Keyword(s):  
Thin Films ◽  
Activation Energy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Silicon Substrates ◽  
Boron Doped Diamond ◽  
Diamond Thin Films ◽  
Hot Filament

AbstractAlthough many researchers have studied boron-doped diamond thin films in the past several years, there have been few reports on the effects of doping CVD-grown diamond films with phosphorous. For this work, polycrystalline diamond thin films were grown by hot filament chemical vapor deposition (HFCVD) on p-type silicon substrates. Phosphorous was introduced into the reaction chamber as an in situ dopant during the growth. The quality and orientation of the diamond thin films were monitored by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Current-voltage (I-V) data as a function of temperature for golddiamond film-silicon-aluminum structures were measured. The activation energy of the phosphorous dopants was calculated to be approximately 0.29 eV.

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