- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Non-epitaxial carrier selective contacts for III-V solar cells: A review
摘要： In the last few years, carrier selective contacts have emerged as a means to reduce the complexities and losses associated with conventional doped p-n junction solar cells. Still, this topic of research is only at its infancy for III-V solar cells, in comparison to other solar cell materials such as silicon, perovskites, chalcogenides, etc. This could be because high quality III-V solar cell materials can be achieved relatively easily using epitaxial growth techniques such as MOCVD (metal organic chemical vapor deposition) and MBE (molecular-beam epitaxy). However, current epitaxial III-V solar cells are very expensive and cannot compete for the terrestrial market, and therefore, researchers are developing alternative growth methods such as thin-film vapor–liquid–solid (TF-VLS), hydride vapor phase epitaxy (HVPE) and closed space vapor transport (CSVT), which are significantly lower in cost compared to epitaxial III-V solar cells. However, at present, these relatively nascent low cost growth methods, face severe optimization issues when it comes to growth of controlled p-n junction, along with heavily doped window and back surface field layers. In such cases, carrier selective contacts can be hugely beneficial. In this review, we cover some of the most recent research on the use of carrier selective contacts for III-V solar cells. Future prospects, challenges, and new device concepts using carrier selective contacts will also be discussed.
关键词： Passivation,III-V solar cell,Heterojunction,Window layer,Carrier selective contact
更新于2025-09-12 10:27:22
-
Efficient Perovskite Solar Cells Enabled by Ions Modulated Grain Boundary Passivation with a Fill Factor Exceeding 84%
摘要： Alkali metal cation modulation toward high-electronic-quality perovskite film requires strictly control over trap densities in the devices. By introducing tailor-made potassium cation (K+) functionalized carbon nanodots (CNDs@K) into the perovskite precursor solution, we succeeded in defects passivation and crystallization control of the perovskite film. X-ray diffraction indicates that the binding effect of carbon dots bounds K+ in the grain boundary and prevents excessive cations from occupying interstitial sites, thereby reducing microstrain of polycrystalline film. Consequently, the synergistic effect of tailored crystal size and suppressed grain boundary defects could reduce charge trap density, facilitate charge generation, and lengthen carrier lifetime, leading to a boosting efficiency of 21.01 % with a high fill factor of 84%. This performance is among of the best reported for carbon dots doped PSCs.
关键词： Perovskite solar cells,Grain boundary passivation,Interstitial occupancy,Grain sizes,CNDs@K
更新于2025-09-11 14:15:04
-
Surface improvement investigation of sol–gel SiO <sub/>2</sub> cladding for waveguide device passivation
摘要： The sol–gel method is a well-known process for SiO2 formation on top of a semiconductor-based waveguide. This method does not require expensive equipment or SiH4 gas. However, it may result in difficulty with wet-etching, which prevents proper current injection into the semiconductor layer. We have investigated the surface condition of sol–gel SiO2 on top of Si, and have confirmed that the main causes of the anti-etching property might be due to the formation of a polymer layer after the curing process. To improve the surface condition, plasma ashing, in addition to 700 °C curing, is proposed. Regular wet etching of SiO2 layer on Si with a ratio of 1800 nm min?1 has been successfully confirmed.
关键词： SiO2,waveguide passivation,plasma ashing,sol–gel method,polymer layer,wet etching
更新于2025-09-11 14:15:04
-
Strategy toward ultra-high-resolution micro-LED displays by bonding interface-engineered vertical stacking and surface passivation
摘要： In this paper, we have proposed the strategy to fulfill the vertically stacked subpixel (VSS) micro-light-emitting diodes (μ-LEDs) for future ultra-high resolution microdisplays. At first, to vertically stack the LED with different colors, we have successfully adopted the bonding interface engineered monolithic integration method by using SiO2/SiNx distributed Bragg reflectors (DBRs). It was found that an intermediate DBR structure can be performed as the bonding layer and the color filter, which can reflect and transmit desired wavelengths the bonding interface. Furthermore, the optically pumped μ-LEDs array with 0.4 μm pitch corresponding to ultra-high-resolution of 63500 PPI was successfully fabricated by using typical semiconductor processing, including electron-beam lithography. Compared with pick-and-place with the limitation of the machine alignment accuracy, there is a significant improvement for fabricating the high-density μ-LEDs. Finally, we have systematically investigated the effects of surface traps by using time-resolved photoluminescence (TRPL) and two-dimensional simulation. These results clearly demonstrated that performance improvements could be possible by employing the optimal passivation techniques according to diminishing the pixel size for low power and highly-efficient microdisplays.
关键词： ultra-high-resolution,micro-LEDs,wafer bonding,distributed Bragg reflectors,surface passivation
更新于2025-09-11 14:15:04
-
Beneficial effects of potassium iodide incorporation on grain boundaries and interfaces of perovskite solar cells
摘要： Grain boundaries and interfacial impurities are the main factors that limit the further development of polycrystalline perovskite solar cells because their existence severely deteriorates the device performance. In order to optimize the efficiency of perovskite solar cells, it is essential to eliminate these defects. In the present work, potassium iodide (KI) is incorporated into the perovskite absorber. KI incorporation improves the crystallinity of the perovskite, increases the grain size, and decreases the contact potential distribution at the grain boundary, which are verified by X-ray diffraction, scanning electronic microscopy and Kelvin probe force microscopy. Besides, the activation energy of the recombination, estimated from the temperature dependent current–voltage of perovskite solar cells, is larger than the bandgap calculated from the temperature coefficient. These suggest that KI incorporation effectively passivates the grain boundaries and interfacial defects. As a result, charge trapping in the absorber as well as the bimolecular and trap-assisted recombination of the device are significantly suppressed. Consequently, the open circuit voltage and fill factor of the incorporated devices are greatly improved, enabling an optimized power conversion efficiency of 19.5%, in comparison with that of 17.3% for the control one. Our work provides an effective strategy of defect passivation in perovskite solar cells by KI incorporation and clarifies the mechanism of the performance optimization of KI incorporated devices.
关键词： potassium iodide,perovskite solar cells,defect passivation,grain boundaries,power conversion efficiency
更新于2025-09-11 14:15:04
-
Highly Efficient Planar Perovskite Solar Cells via Acid-assisted Surface Passivation
摘要： Low-temperature solution-processed SnO2-based perovskite solar cells (PSCs) have achieved great progresses recently, but it still suffers from a critical drawback due to the defects at SnO2/perovskite interface. Herein, we report a facile acetic acid post-treatment strategy to effectively passivate the surface defects. Under the optimal concentration of acetic acid modification, the average power conversion efficiency (PCE) of the planar-type triple cation PSCs is greatly increased from 18.57% to 20.33%. The champion device shows a PCE of 20.56%. In addition, the universality of this passivation strategy is double confirmed by achieving an enhanced average PCE from 19.52% to 21.64% for sequential method deposited dual cation PSCs, with a leading PCE of 21.95%. Our work demonstrates an effective passivation strategy for SnO2-based planar-type PSCs, which will benefit the development of high-efficient PSCs.
关键词： defect passivation,interface,perovskite solar cells,tin oxide
更新于2025-09-11 14:15:04
-
Interfacial Modification and Defect Passivation by Crosslinking Interlayer for Efficient and Stable CuSCN-Based Perovskite Solar Cell
摘要： Study of the inorganic hole-transport layer (HTL) in perovskite solar cell (PSC) is gathering attention due to the drawback of conventional PSC design, where the organic HTL with salt dopants majorly participates in the degradation mechanisms. On the other hand, inorganic HTL secures better stability, while it offers difficulties in the deposition and interfacial control to realize high-performing devices. In this study, we demonstrate polydimethylsiloxane (PDMS) as an ideal polymeric interlayer which prevents the interfacial degradation, and improves both photovoltaic performance and stability of CuSCN-based PSC by its crosslinking behavior. Surprisingly, the PDMS polymers are identified to form chemical bonds with perovskite and CuSCN, as shown by Raman spectroscopy. This novel crosslinking interlayer of PDMS enhances the hole-transporting property at the interface and passivates the interfacial defects, realizing the PSC with high power-conversion efficiency over 19%. Furthermore, the utilization of PDMS interlayer greatly improves the stability of solar cells against both humidity and heat, by mitigating the interfacial defects and interdiffusion. The PDMS-interlayered PSCs retained over 90% of the initial efficiencies, both after 1000 h under ambient condition (unencapsulated) and after 500 h under 85°C/85% relative humidity (encapsulated).
关键词： Crosslinking Interlayer,Inorganic Hole-Transport Layer,Defect Passivation,Stability,Perovskite Solar Cell
更新于2025-09-11 14:15:04
-
AIP Conference Proceedings [AIP Publishing 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Fes, Morocco (25–27 March 2019)] 15th International Conference on Concentrator Photovoltaic Systems (CPV-15) - Low-temperature silicon surface passivation for bulk lifetime studies based on Corona-charged Al2O3
摘要： Bulk lifetime studies of crystalline silicon wafers, e.g. with the aim of studying the light-induced degradation and regeneration behavior, require low-temperature surface passivation schemes that do not alter the silicon bulk properties, e.g. through hydrogenation. Aluminum oxide (Al2O3) can provide an excellent and stable surface passivation, however, in order to achieve the best possible surface passivation, an annealing step at ~400°C is typically required, which has been found to alter the bulk properties of some silicon materials. Hence, in this contribution we examine the possibility of passivating the silicon surface using Al2O3 layers that have seen a much lower thermal budget. We demonstrate that we are able to achieve an excellent silicon surface passivation using atomic-layer-deposited Al2O3 with measured effective surface recombination velocities Seff as low as 1.3 cm/s without exceeding a temperature of 250°C. We are able to achieve such excellent low-temperature passivation by applying a post-deposition annealing step at 250°C in combination with the deposition of negative Corona charges on the Al2O3 surface. For samples annealed at only 220°C, we still reach very low Seff values of 2 cm/s after deposition of negative Corona charges. We demonstrate that the Corona-charged low-temperature Al2O3 passivation shows only a slight degradation from an Seff of 1.6 cm/s to an Seff of 5 cm/s after 218 days of storage. Even without any post-deposition anneal and only negative Corona charges deposited, we achieve stable Seff values of 15 cm/s. As an alternative to Corona charging, a short exposure to intense UV light (λ = 395 nm) also significantly improves the surface passivation quality of low-temperature-annealed Al2O3-passivated silicon samples. However, the best surface passivation for the latter method is limited to an Seff value of 6.6 cm/s, which is still quite reasonable for bulk lifetime studies.
关键词： bulk lifetime studies,Al2O3,Corona charging,silicon surface passivation,low-temperature annealing
更新于2025-09-11 14:15:04
-
Reversible PL Tuning by Defect Passivation via Laser Irradiation on Aged Monolayer MoS2
摘要： Atomically thin (1L) MoS2 emerged as a direct band gap semiconductor with potential optical applications. The photoluminescence (PL) of 1L-MoS2 degrades due to aging related defect formation. The passivation of these defects leads to substantial improvement in optical properties. Here we report the enhancement of PL on aged 1L-MoS2 by laser treatment. Using photoluminescence and Raman spectroscopy in a controlled gas environment, we show the enhancement is associated with efficient adsorption of oxygen on existing sulfur vacancies preceded by removal of adsorbates from the sample’s surface. Oxygen adsorption depletes negative charges, resulting in suppression of trions and improved neutral exciton recombination. The result is a 6-8 fold increase in PL emission. The laser treatment in this work does not cause any measurable damage to the sample as verified by Raman spectroscopy, which is important for practical applications. Surprisingly, the observed PL enhancement is reversible by both vacuum and ultrafast femtosecond excitation. While the former approach allows switching a designed micro pattern on the sample ON and OFF, the latte provides a controllable mean for accurate PL tuning, which is highly desirable for optoelectronic and gas sensing applications.
关键词： Raman,Exciton,Laser Annealing,Oxygen,Photoluminescence,Reversible Defect passivation,MoS2
更新于2025-09-11 14:15:04
-
In-situ Process to Form Passivated Tunneling Oxides for Front-surface Field in Rear-emitter Silicon Heterojunction Solar Cells
摘要： A novel approach involving CO2 plasma treatment of intrinsic hydrogenated amorphous silicon was developed to form ultra-thin silicon oxide (SiOx) layers, that is, passivated tunneling layers (PTLs), for the fabrication of passivated tunneling contacts. These contacts were formed by depositing the PTL/n-type hydrogenated nano-crystalline layer (nc-Si:H(n))/c-Si(n) stacks. The results indicated that a higher CO2 plasma treatment pressure was preferred for the formation of oxygen-richer components in the silicon oxide films, with Si2+, Si3+, and Si4+ peaks, and a smoother PTL/c-Si heterointerface. The PTLs with higher oxidation states and lower surface roughness exhibited advantages for the c-Si surface passivation, with a maximum implied open-circuit voltage of approximately 743 mV. The lowest contact resistivity of approximately 60 mΩcm2 was obtained using nc-Si:H(n)/PTL/c-Si(n) as the passivated tunneling contact. Most importantly, the in-situ process can help prevent the contamination of the heterointerface during device fabrication processes.
关键词： Passivated tunneling layer (PTL),Silicon oxide (SiOx),CO2 plasma treatment,Silicon surface passivation
更新于2025-09-11 14:15:04