scholarly journals Electrical TCAD Study of the Low-Voltage Avalanche-Mode Superjunction LED

2021 ◽  
Author(s):  
Raymond Hueting ◽  
Satadal Dutta ◽  
Hidde de Vries ◽  
Anne-Johan Annema
Keyword(s):  
Optical Interconnects ◽  
Low Voltage ◽  
Light Emitting Diode ◽  
Reducing Power ◽  
Constant Field ◽  
Uniform Field ◽  
Charge Balance ◽  
Light Emitting ◽  
Balance Condition ◽  
Tcad Simulation

The CMOS silicon avalanche-mode light-emitting diode (AMLED) has emerged as a potential light source for monolithic optical interconnects. Earlier we presented a superjunction light-emitting diode (SJLED) that offers a higher electroluminescent intensity compared to a conventional AMLED because of its more uniform field distribution. However, for reducing power consumption low-voltage (< 15V) SJLEDs are desired, not explored before. In this work we present a TCAD simulation feasibility study of the low-voltage SJLED for various doping concentrations and device dimensions. The results show that for obtaining a constant field, approximately a ten-fold more aggressive charge balance condition in the SJLED is estimated than traditionally reported. This is important for establishing a guideline to realize optimized RESURF and SJLEDs in the ever-shrinking advanced CMOS nodes.

scholarly journals Electrical TCAD Study of the Low-Voltage Avalanche-Mode Superjunction LED

2021 ◽  
Author(s):  
Raymond Hueting ◽  
Satadal Dutta ◽  
Hidde de Vries ◽  
Anne-Johan Annema
Keyword(s):  
Optical Interconnects ◽  
Low Voltage ◽  
Light Emitting Diode ◽  
Reducing Power ◽  
Constant Field ◽  
Uniform Field ◽  
Charge Balance ◽  
Light Emitting ◽  
Balance Condition ◽  
Tcad Simulation

The CMOS silicon avalanche-mode light-emitting diode (AMLED) has emerged as a potential light source for monolithic optical interconnects. Earlier we presented a superjunction light-emitting diode (SJLED) that offers a higher electroluminescent intensity compared to a conventional AMLED because of its more uniform field distribution. However, for reducing power consumption low-voltage (< 15V) SJLEDs are desired, not explored before. In this work we present a TCAD simulation feasibility study of the low-voltage SJLED for various doping concentrations and device dimensions. The results show that for obtaining a constant field, approximately a ten-fold more aggressive charge balance condition in the SJLED is estimated than traditionally reported. This is important for establishing a guideline to realize optimized RESURF and SJLEDs in the ever-shrinking advanced CMOS nodes.

scholarly journals The Photoluminescence Behaviors of a Novel Reddish Orange Emitting Phosphor CaIn2O4:Sm3+Codoped with Zn2+or Al3+Ions

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Jing Gou ◽  
Dongyang Zhang ◽  
Binxun Yu ◽  
Jing Wang ◽  
Shengzhong Liu
Keyword(s):  
Light Emitting Diode ◽  
Luminescence Properties ◽  
Charge Balance ◽  
Transfer Energy ◽  
Light Emitting ◽  
Ultraviolet Excitation ◽  
Near Ultraviolet ◽  
Chromaticity Coordinates ◽  
Charge Transfer Absorption Band ◽  
Reddish Orange

A novel reddish orange phosphor CaIn2O4:Sm3+codoped with Zn2+or Al3+ions was prepared by solid state reaction and their luminescence properties were investigated under near ultraviolet excitation. The strategy of Zn2+or Al3+ions codoping was used with the aim to improve the luminescence properties of CaIn2O4:Sm3+, but the concrete effects of the two ions is different. The introduction of Zn2+ions can produceZnIn'defects that favor charge balance in CaIn2O4:Sm3+to facilitate its photoluminescence. The effect of Al3+ions codoping can effectively transfer energy from charge-transfer absorption band to characteristic transition of Sm3+ions, utilizing more energy from host absorption for the photoluminescence of Sm3+ions. Based on these mechanisms, the luminescence intensity of CaIn2O4:0.6%Sm3+was enhanced to 1.59 times and 1.51 times when codoping amount of Zn2+and Al3+ions reached 0.6%. However, the chromaticity coordinates of CaIn2O4:0.6%Sm3+almost did not have any changes after Zn2+ions or Al3+ions codoping; those are still located at reddish orange region. The excellent luminescence properties of CaIn2O4:0.6%Sm3+,0.6%Zn2+and CaIn2O4:0.6%Sm3+,0.6%Al3+demonstrate that they both have potential application value as new-style reddish orange phosphors on light-emitting diode.

scholarly journals A Wind Powered, White LED Lighting System for the Kibera Slum of Nairobi

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
Brian Thomas
Keyword(s):  
Service Learning ◽  
Transmission Lines ◽  
Alternative Energy ◽  
Engineering Students ◽  
Low Voltage ◽  
Community Organization ◽  
Light Emitting Diode ◽  
Circuit Breaker ◽  
Governmental Organization ◽  
Light Emitting

A multidisciplinary team of engineering students traveled to Nairobi, Kenya in May 2006 to implement a service learning project between academic sessions. Low power, white light emitting diode (WLED) based lighting devices were designed and built by student participants and members of the student organization Engineers with a Mission during the months preceding the trip. Photometric performance and power consumption data are given for these devices, which were subsequently installed in seventeen homes in the large and infamous Kibera slum. A locally manufactured, technologically appropriate wind generator was purchased and installed to charge a single, centrally located deep cycle battery. Power from this battery was distributed to the LED-based lights through a student designed and built circuit breaker panel and a radial network of indoor/outdoor extension cords that served as low voltage transmission lines. The project provided a learning environment for alternative energy techniques, appropriate technologies, global and multicultural awareness, poverty apprehension, the realities of project implementation, and the social responsibility of those in the engineering profession. A network of Kenyan organizations consisting of a university, a non-governmental organization, a small business, and a community organization, was formed to facilitate sustainability and provide ongoing analysis and maintenance.

Investigation of 4,4′- bis [(N carbazole) styryl] biphenyl (BSB4) for a pure blue fluorescent OLED with enhanced efficiency nearing the theoretical limit

2022 ◽  
Author(s):  
Dhruvajyoti Barah ◽  
Subhamoy Sahoo ◽  
Naga Sai Manoj Inaganti ◽  
Haripriya Kesavan ◽  
Jayeeta Bhattacharyya ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Blue Emission ◽  
Blue Shift ◽  
Optical Simulation ◽  
Charge Balance ◽  
Theoretical Limit ◽  
Optical Interference ◽  
Device Structure ◽  
Light Emitting ◽  
Emissive Layer

Abstract 4,4′-bis[(N-carbazole) styryl] biphenyl (BSB4 or BSBCz) is one of the widely studied organic fluorescent materials for blue organic electroluminescent devices in the recent times. In this work, BSB4 is used as a guest material to construct the host-guest matrix for the emissive layer (EML) of a pure blue fluorescent organic light-emitting diode (OLED). A pure blue emission suitable for display application with a Commission Internationale de l’Eclairage (CIE) coordinate of (0.147, 0.070) is achieved by the blue-shift of the emission spectrum of the host-guest matrix from that of the pristine guest (BSB4) molecules. The optimization of OLED structures is carried out by considering (i) charge balance in the emissive layer for high exciton density, and (ii) optical interference of generated light in the organic layers for increased light outcoupling. A thorough comparative study on the use of different combinations of widely used hole and electron transport layers to obtain charge balance in the EML of the OLED, thereby enhancing the external quantum efficiency (EQE) is shown. Optical interference effects in the fabricated OLEDs are analyzed by optical simulation of each device structure by transfer matrix method (TMM). With the optimized device structures, we are able to overcome the 2% EQE limit that has been reported so far for blue fluorescent OLEDs with BSB4 as light emitting material and achieve a maximum EQE of 4.08%, which is near to the theoretical limit of EQE for fluorescent OLEDs.

scholarly journals Influence of Annealing Temperature on Weak-Cavity Top-Emission Red Quantum Dot Light Emitting Diode

Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1639 ◽  
Author(s):  
Chun-Yu Lee ◽  
Ya-Pei Kuo ◽  
Peng-Yu Chen ◽  
Hsieh-Hsing Lu ◽  
Ming Yi Lin
Keyword(s):  
Annealing Temperature ◽  
Light Emitting Diode ◽  
Hole Injection ◽  
Performance Measurements ◽  
Charge Balance ◽  
Light Emitting ◽  
Annealing Temperatures ◽  
Single Carrier ◽  
Maximum Current ◽  
Mg Doped

In this report, we show that the annealing temperature in QDs/Mg-doped ZnO film plays a very important role in determining QLEDs performance. Measurements of capacitance and single carrier device reveal that the change of the device efficiency with different annealing temperatures is related to the balance of both electron and hole injection. A comparison of annealing temperatures shows that the best performance is demonstrated with 150 °C-annealing temperature. With the improved charge injection and charge balance, a maximum current efficiency of 24.81 cd/A and external quantum efficiency (EQE) of 20.09% are achievable in our red top-emission QLEDs with weak microcavity structure.

scholarly journals Enhancement of Efficiency and Lifetime of Blue Organic Light-Emitting Diodes Using Two Dopants in Single Emitting Layer

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Jianning Yu ◽  
Na Wei ◽  
Chong Li ◽  
Bin Wei ◽  
Wei Huang ◽  
...  
Keyword(s):  
Indium Tin Oxide ◽  
Light Emitting Diode ◽  
Hole Mobility ◽  
Organic Light Emitting Diodes ◽  
Charge Balance ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light ◽  
Operational Lifetime ◽  
Exciton Recombination

We have demonstrated efficient blue organic light-emitting diode with the structure of indium tin oxide/4,4′,4″-tris(N-(2-naphthyl)-N-phenyl-amino)triphenylamine/1,4-bis[N-(1-naphthyl)-N′-phenylamino]-4,4′-diamine/9,10-di(2-naphthyl)anthracene (ADN): 1-4-di-[4-(N,N-di-phenyl)amino]styryl-benzene (DSA-ph) 3 wt%/tris-(8-hydroxyquinoline)aluminum/LiF/Al. Improved efficiencies and longer operational lifetime were obtained by codoping a styrylamine-based dopant BD-3 (0.1 wt%) into the emitting layer of ADN doped with DSA-ph compared to the case of non-codoping. This was due to the improved charge balance and expansion of exciton recombination zone. The better charge balance was obtained by reducing the electron mobility of ADN which was higher than the hole mobility in the case of non-codoping.

High-efficiency, low-voltage phosphorescent organic light-emitting diode devices with mixed host

2008 ◽  
Vol 104 (9) ◽  
pp. 094501 ◽  
Author(s):  
Marina E. Kondakova ◽  
Thomas D. Pawlik ◽  
Ralph H. Young ◽  
David J. Giesen ◽  
Denis Y. Kondakov ◽  
...  
Keyword(s):  
High Efficiency ◽  
Low Voltage ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
Organic Light Emitting Diode ◽  
Organic Light
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