scholarly journals Understanding of Molecular Contribution of Quinhydrone/Methanol Organic Passivation for Improved Minority Carrier Lifetime on Nanostructured Silicon Surface

2019 ◽  
Vol 9 (18) ◽  
pp. 3645
Author(s):  
Jea-Young Choi

In this report, we present a study of the quinhydrone/methanol (QHY/MeOH) organic passivation technique for a silicon (Si) surface. The roles of p-benzoquinone (BQ) and hydroquinone (HQ), which make up QHY, in controlling the uniformity and coverage of the passivation layer as well as the minority carrier lifetime (τeff) of Si were investigated. The uniformity and coverage of the passivation layer after treatment with diverse mixture ratios of BQ and HQ in MeOH were studied with two different atomic force microscope (AFM) techniques, namely tunneling mode (TUNA) and high-resolution tapping mode AFM (HR-AFM). In addition, the τeff and surface potential voltages (SPV) of passivated surfaces were measured to clarify the relationship between the morphologies of the passivation layers and degrees of surface band bending. The molecular interactions between BQ and HQ in MeOH were also analyzed using Fourier-transform infrared spectroscopy (FT-IR). In our study, we successfully demonstrated the role of each molecule for effective Si surface passivation with BQ working as a passivation agent and HQ contributing as a proton (H+) donator to BQ for accelerating the passivation rate. However, our study also clearly revealed that HQ could also hinder the formation of a conformal passivation layer, which raises an issue for passivation over complex surface geometry, especially a nanostructured surface.

2007 ◽  
Vol 131-133 ◽  
pp. 431-436 ◽  
Author(s):  
J.M. Rafí ◽  
L. Cardona-Safont ◽  
M. Zabala ◽  
C. Boulord ◽  
F. Campabadal ◽  
...  

In order to identify an appropriate low-temperature surface passivation that could be used for bulk lifetime estimation of high resistivity (HR) (> 1 k·cm) silicon for radiation detectors, different passivating layers were evaluated on n-type and p-type standard Czochralski (CZ), HR magnetic CZ and HR float zone (FZ) substrates. Minority carrier lifetime measurements were performed by means of a μW-PCD set-up. The results show that SiNx PECVD layers deposited at low temperatures (≤ 250°C) may be used to evaluate the impact of different processing steps and treatments on the substrate characteristics for radiation detectors. First results are obtained about a preliminary thermal treatment experiment to evaluate the thermal stability of the passivating layers, as well as the potential impact of the generation of thermal donors on minority carrier lifetime.


2010 ◽  
Vol 55 (17) ◽  
pp. 1828-1833 ◽  
Author(s):  
Feng Li ◽  
ZhongQuan Ma ◽  
XiaJie Meng ◽  
Peng Lü ◽  
ZhengShan Yu ◽  
...  

2014 ◽  
Vol 936 ◽  
pp. 603-606
Author(s):  
Yin Wang ◽  
Wei Li ◽  
An Ran Guo ◽  
Feng Yu ◽  
Jian He ◽  
...  

Surface passivation of c-Si by a-Si:H thin films has been studied. In this paper, the minority carrier lifetime of 345μs (from 85μs) is obtained at optimal hydrogen flow rate (8.0sccm) by using RF-magnetron sputtering method.


2016 ◽  
Vol 703 ◽  
pp. 230-234
Author(s):  
Yu Ren Xiang ◽  
Chun Lan Zhou ◽  
Wen Jing Wang

Aluminum oxide (Al2O3) films have been wildly investigated due to the excellent surface passivation for the electrical device. Both hydrogen-terminated and pre-oxidized silicon surfaces were prepared before Al2O3 films deposition. Combining chemical environment analysis with the effective minority lifetime data, the effect of the surface conditions on the Al2O3 films passivation was discussed. The HF sample with hydrogen-terminated substrate surface had a higher minority carrier lifetime (about 721 μs) than the H2SO4+H2O2 sample with pre-oxidized substrate surface (about 631 μs). The H atoms played an important role in improving the passivation effect. And the importance of the interfacial oxide layer to Al2O3 films passivation was validated too.


MRS Advances ◽  
2016 ◽  
Vol 1 (50) ◽  
pp. 3379-3390
Author(s):  
Sneha Banerjee ◽  
Rajendra Dahal ◽  
Ishwara Bhat

ABSTRACT Three II-VI wide bandgap compound semiconductors have been investigated for surface passivation of various photovoltaic devices. First part of this work focuses on the surface passivation of HgCdTe IR detectors using CdTe. A new metalorganic chemical vapor deposition (MOCVD) process has been developed that involves depositing CdTe films at much lower temperature (< 175°C) than the conventional processes used till now. Deposition rate as high as 420nm/h was obtained using this novel experimental setup. Favorable conformal coverage on high aspect ratio HgCdTe devices along with a significant minority carrier lifetime improvement was obtained. Another II-VI semiconductor, namely, CdS was investigated as a surface passivant for HgCdTe IR detectors. It was deposited by MOCVD as well as atomic layer deposition (ALD) and was studied for optimal conformal coverage on high aspect ratio structures. Surface passivation of p-type Si wafer has also been demonstrated using p-ZnTe grown by MOCVD, for possible application in solar cells. Preliminary work showed a remarkable improvement in the minority carrier lifetime of Si light absorbing layer after passivation with a thin layer of ZnTe.


2013 ◽  
Vol 652-654 ◽  
pp. 901-905 ◽  
Author(s):  
Jing Wei Chen ◽  
Lei Zhao ◽  
Hong Wei Diao ◽  
Bao Jun Yan ◽  
Su Zhou ◽  
...  

The effective minority carrier lifetime (τeff) depends upon the quality of surface passivation, which by means of the microwave photoconductance decays (μPCD) method. The effective minority carrier lifetime (τeff) cannot reveal the real bulk lifetime of minority carriers (τb) . We have applied iodine-ethanol (I-E) treatment to silicon surface at different molar concentrations and shown that the effective concentrations ranges was 0.08mol/L~0.16 mol/L, the maximum The effective minority carrier lifetime (τeff) of n-type monocrystalline and p-type monocrystalline was 973.71μs and 362.6μs, respectively. We also accurately evaluate the bulk lifetime of minority carriers by measured with different thickness of silicon substrate.


2021 ◽  
Vol 11 (8) ◽  
pp. 3527
Author(s):  
Jian Lin ◽  
Hongsub Jee ◽  
Jangwon Yoo ◽  
Junsin Yi ◽  
Chaehwan Jeong ◽  
...  

We report the effects of H2S passivation on the effective minority carrier lifetime of crystalline silicon (c-Si) wafers. c-Si wafers were thermally annealed under an H2S atmosphere at various temperatures. The initial minority carrier lifetime (6.97 μs) of a c-Si wafer without any passivation treatments was also measured for comparison. The highest minority carrier lifetime gain of 2030% was observed at an annealing temperature of 600 °C. The X-ray photoelectron spectroscopy analysis revealed that S atoms were bonded to Si atoms after H2S annealing treatment. This indicates that the increase in minority carrier lifetime originating from the effect of sulfur passivation on the silicon wafer surface involves dangling bonds.


2018 ◽  
Vol 13 (10) ◽  
pp. 1591-1597
Author(s):  
Rajkumar Sahu ◽  
Srikanta Palei ◽  
Jaeho Choi ◽  
Keunjoo Kim

We investigated the surface passivation of silicon solar cells by nitrogen ion implantation. The nitrogen ion was implanted with the energy of 20 keV at a twist angle of 22.5° from the Si 〈100〉 direction and a tilt angle of 7°. The ion concentration was varied at 1013, 1014, and 1015 N+/cm2. The implanted cell showed the implanted region located below the anti-reflection coating layer. For the low dose cell of 1013 N+/cm2, the nitrogen ion implantation showed increased quantum efficiency, minority carrier lifetime, and conversion efficiency compared to the reference cell. However, as the ion dose was increased, the quantum efficiency, minority carrier lifetime, photoreflectance, and cell conversion efficiency of the fabricated cell decreased. This indicates that nitrogen ion implantation can passivate the surface to increase the cell conversion efficiency with a critical dose of ions.


Sign in / Sign up

Export Citation Format

Share Document