Semiconductor Science and Technology最新文献_第6页

Quantification of losses in bent waveguides within DBR-RW laser diodes emitting at 785 nm 对波长 785 纳米的 DBR-RW 激光二极管内弯曲波导中的损耗进行量化

Semiconductor Science and Technology Pub Date : 2024-02-06 DOI: 10.1088/1361-6641/ad26a6

L. S. Theurer, J. Koester, A. Müller, M. Maiwald, Andrea Knigge, B. Sumpf, G. Tränkle

{"title":"Quantification of losses in bent waveguides within DBR-RW laser diodes emitting at 785 nm","authors":"L. S. Theurer, J. Koester, A. Müller, M. Maiwald, Andrea Knigge, B. Sumpf, G. Tränkle","doi":"10.1088/1361-6641/ad26a6","DOIUrl":"https://doi.org/10.1088/1361-6641/ad26a6","url":null,"abstract":"\u0000 An experimental study of straight and bent distributed Bragg reflector (DBR) ridge waveguide (RW) lasers and Fabry-Pérot RW lasers emitting at 785 nm is presented. To determine the losses introduced by the bent waveguides within DBR-RW lasers, different laser designs were manufactured and characterized. The bent waveguides investigated here within DBR-RW laser diodes are sine-shaped S-bends. S-bends with three different lateral offsets are manufactured. The experimental characterization of Fabry-Pérot lasers and the straight DBR-RW lasers with different coatings at the rear facet enables a rough estimation of the losses caused by the DBR grating and the determination of the DBR reflectivity. Furthermore, additional losses in the bent DBR-RW lasers caused by the S-bend (i.e. radiation and scattering losses) are quantified by comparing them to the straight DBR-RW lasers. Within the active resonator, the S-bend losses amount to αBend = 0.6 cm-1 (αBend = 0.5 dB) for the smallest manufactured lateral S-bend offset H = 40 µm. For both straight and bent DBR-RW lasers spectrally narrow single-mode emission is obtained. A lateral beam width of 3.8 µm (using second moments) and a lateral far-field angle of about 18° and 19.5° (using second moments) for the straight and S-bend DBR-RW are measured, respectively. This gives a lateral beam propagation ratio of 1.2 and 1.3 (using second moments) for straight and S-bend DBR-RW, respectively. The radiation loss in dependency of the lateral S-bend offset is simulated and compared to experimentally estimated S-bend losses for bent DBR-RW lasers (H = 40 µm, H = 60 µm and H = 70 µm).","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"101 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139801278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantification of losses in bent waveguides within DBR-RW laser diodes emitting at 785 nm 对波长 785 纳米的 DBR-RW 激光二极管内弯曲波导中的损耗进行量化

Semiconductor Science and Technology Pub Date : 2024-02-06 DOI: 10.1088/1361-6641/ad26a6

L. S. Theurer, J. Koester, A. Müller, M. Maiwald, Andrea Knigge, B. Sumpf, G. Tränkle

{"title":"Quantification of losses in bent waveguides within DBR-RW laser diodes emitting at 785 nm","authors":"L. S. Theurer, J. Koester, A. Müller, M. Maiwald, Andrea Knigge, B. Sumpf, G. Tränkle","doi":"10.1088/1361-6641/ad26a6","DOIUrl":"https://doi.org/10.1088/1361-6641/ad26a6","url":null,"abstract":"\u0000 An experimental study of straight and bent distributed Bragg reflector (DBR) ridge waveguide (RW) lasers and Fabry-Pérot RW lasers emitting at 785 nm is presented. To determine the losses introduced by the bent waveguides within DBR-RW lasers, different laser designs were manufactured and characterized. The bent waveguides investigated here within DBR-RW laser diodes are sine-shaped S-bends. S-bends with three different lateral offsets are manufactured. The experimental characterization of Fabry-Pérot lasers and the straight DBR-RW lasers with different coatings at the rear facet enables a rough estimation of the losses caused by the DBR grating and the determination of the DBR reflectivity. Furthermore, additional losses in the bent DBR-RW lasers caused by the S-bend (i.e. radiation and scattering losses) are quantified by comparing them to the straight DBR-RW lasers. Within the active resonator, the S-bend losses amount to αBend = 0.6 cm-1 (αBend = 0.5 dB) for the smallest manufactured lateral S-bend offset H = 40 µm. For both straight and bent DBR-RW lasers spectrally narrow single-mode emission is obtained. A lateral beam width of 3.8 µm (using second moments) and a lateral far-field angle of about 18° and 19.5° (using second moments) for the straight and S-bend DBR-RW are measured, respectively. This gives a lateral beam propagation ratio of 1.2 and 1.3 (using second moments) for straight and S-bend DBR-RW, respectively. The radiation loss in dependency of the lateral S-bend offset is simulated and compared to experimentally estimated S-bend losses for bent DBR-RW lasers (H = 40 µm, H = 60 µm and H = 70 µm).","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"71 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139860870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Franz‐Keldysh effect in the optical absorption spectrum of TlGaSe2 layered semiconductor caused by charged native defects 带电原生缺陷导致 TlGaSe2 层状半导体光吸收光谱中的弗朗兹-凯尔迪什效应

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad255b

Serdar Gören, Yasin Şale, MirHasan Yunus Seyidov

{"title":"The Franz‐Keldysh effect in the optical absorption spectrum of TlGaSe2 layered semiconductor caused by charged native defects","authors":"Serdar Gören, Yasin Şale, MirHasan Yunus Seyidov","doi":"10.1088/1361-6641/ad255b","DOIUrl":"https://doi.org/10.1088/1361-6641/ad255b","url":null,"abstract":"\u0000 The Franz-Keldysh effect in the optical absorption edge of bulk TlGaSe2 layered semiconductor poled under an external electric field was investigated in the present work. The Franz-Keldysh shift below the optical band gap absorption region, as well as the quasi-periodic oscillations above the fundamental band gap of TlGaSe2, were observed. The measured changes in optical light absorption of the TlGaSe2 sample were revealed after poling processing. The poling technique is used to produce the built-in internal electric field within the TlGaSe2 semiconductor. The frozen-in internal electric field in TlGaSe2 was experimentally monitored through changes in the line–shape of the absorption spectra at the fundamental band edge. The observed results are accurately fitted with the theoretical line-shape function of the Franz - Keldysh absorption tail below the bandgap of TlGaSe2 and quasi-periodic oscillations above the bandgap. A good agreement between theoretical and experimental results took place. The present study demonstrated that the Franz - Keldysh effect can be used to identify and characterize the localized internal electric fields originating from the electrically active native imperfections in the TlGaSe2 crystals.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"44 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139871392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improved light extraction efficiency of AlGaN DUV light emitting diodes using Al/MgF2-based highly reflective film 使用基于 Al/MgF2 的高反射膜提高 AlGaN DUV 发光二极管的光提取效率

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad255a

Peishan Li, Xiaoyue Huang, Yuqing Yang, Zhenghao Xia, Qiao Wang, Hang Chen, Xingfu Wang

{"title":"Improved light extraction efficiency of AlGaN DUV light emitting diodes using Al/MgF2-based highly reflective film","authors":"Peishan Li, Xiaoyue Huang, Yuqing Yang, Zhenghao Xia, Qiao Wang, Hang Chen, Xingfu Wang","doi":"10.1088/1361-6641/ad255a","DOIUrl":"https://doi.org/10.1088/1361-6641/ad255a","url":null,"abstract":"\u0000 AlGaN DUV light emitting diodes (DUV-LEDs) (275 nm emission) are safe, eco-friendly and smart alternatives for inactivating viruses and bacteria. However, DUV-LEDs suffer from the main bottleneck of low external quantum efficiencies, which are strongly associated with the low light extraction efficiency caused by the strong optical polarisation of Al-rich AlGaN. Optical simulation results show that the luminous intensity of DUV-LEDs was increased by 10% owing to the synergistic effect of the sidewalls and substrates. The optical power of DUV-LEDs was increased to 16.8%, the far-field pattern was expanded to 130 degrees and the emission intensity was more focus on the central region, proving that the highly reflective sidewalls and substrates could re-direct the sideways-travelling photons for extraction. Moreover, we also investigated the reflective mechanism of Al/MgF2 layers. Optimise refractive index distribution of Al/MgF2 layers could change the electric field intensity to improve the reflectivity. Meanwhile, the temperature of the sample after coating were significantly reduced by 7.33%. Thermal radiation benefits and the high stability of bonding interface are the main reasons to reduce the temperature of DUVLEDs after Al/MgF2 coating. The present strategy is proposed from the view of the chip fabrication, which is cost-effective, able to be manufactured at a large scale.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"36 S23","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139810259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving the structural performance of low-temperature sputtered AlN on silicon substrate 提高硅衬底上低温溅射氮化铝的结构性能

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad2559

Yuchi Luo, Ye Yuan, Zhiwen Liang, Tianren Cai, Hengyi Yin, Yichen Zhao, Hongmeng Zhang, Jiakang Cao, Wenting Wan, Yanda Ji, Anli Yang, Qi Wang, Mingming Hao

{"title":"Improving the structural performance of low-temperature sputtered AlN on silicon substrate","authors":"Yuchi Luo, Ye Yuan, Zhiwen Liang, Tianren Cai, Hengyi Yin, Yichen Zhao, Hongmeng Zhang, Jiakang Cao, Wenting Wan, Yanda Ji, Anli Yang, Qi Wang, Mingming Hao","doi":"10.1088/1361-6641/ad2559","DOIUrl":"https://doi.org/10.1088/1361-6641/ad2559","url":null,"abstract":"\u0000 Preparing high-quality AlN films at low temperatures is always highly demanded in plenty of application-fields, despite the high temperature is always necessary to enable the AlN crystallization. Therefore, improving the structural properties at low temperature is still challenging in the field. In the present work, the metal organic chemical vapor deposition (MOCVD) grown AlN nucleation layer is employed to improve the crystallinity and morphology of sputtered AlN on 6-inch Si (111) substrate at the temperature even as low as 100℃ where it is not principally possible to achieve the crystallization of sputtered AlN. When compared with the as-sputtered AlN prepared even at 650℃, it is found that the full width at half maximum (FWHM) of AlN (002) X-ray rocking curves is intensively decreased to 0.96° from 1.61°, and such a reduction indicates that the screw dislocation density is decreased from 7.31×1010 down to 2.14×1010/cm2. In addition to the crystallinity, the morphology is also obviously improved that the root-mean-square (RMS) roughness is reduced from 4.99 nm down to 0.83 nm in a scanned area of 3×3 μm2 through introducing AlN nucleation. Therefore, such a combination highlights the contribution of AlN nucleation grown by MOCVD in improving the structural properties of low-temperature sputtered AlN layer which is compatible with the manufacturing of Si integrated circuits.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139870100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving the structural performance of low-temperature sputtered AlN on silicon substrate 提高硅衬底上低温溅射氮化铝的结构性能

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad2559

Yuchi Luo, Ye Yuan, Zhiwen Liang, Tianren Cai, Hengyi Yin, Yichen Zhao, Hongmeng Zhang, Jiakang Cao, Wenting Wan, Yanda Ji, Anli Yang, Qi Wang, Mingming Hao

{"title":"Improving the structural performance of low-temperature sputtered AlN on silicon substrate","authors":"Yuchi Luo, Ye Yuan, Zhiwen Liang, Tianren Cai, Hengyi Yin, Yichen Zhao, Hongmeng Zhang, Jiakang Cao, Wenting Wan, Yanda Ji, Anli Yang, Qi Wang, Mingming Hao","doi":"10.1088/1361-6641/ad2559","DOIUrl":"https://doi.org/10.1088/1361-6641/ad2559","url":null,"abstract":"\u0000 Preparing high-quality AlN films at low temperatures is always highly demanded in plenty of application-fields, despite the high temperature is always necessary to enable the AlN crystallization. Therefore, improving the structural properties at low temperature is still challenging in the field. In the present work, the metal organic chemical vapor deposition (MOCVD) grown AlN nucleation layer is employed to improve the crystallinity and morphology of sputtered AlN on 6-inch Si (111) substrate at the temperature even as low as 100℃ where it is not principally possible to achieve the crystallization of sputtered AlN. When compared with the as-sputtered AlN prepared even at 650℃, it is found that the full width at half maximum (FWHM) of AlN (002) X-ray rocking curves is intensively decreased to 0.96° from 1.61°, and such a reduction indicates that the screw dislocation density is decreased from 7.31×1010 down to 2.14×1010/cm2. In addition to the crystallinity, the morphology is also obviously improved that the root-mean-square (RMS) roughness is reduced from 4.99 nm down to 0.83 nm in a scanned area of 3×3 μm2 through introducing AlN nucleation. Therefore, such a combination highlights the contribution of AlN nucleation grown by MOCVD in improving the structural properties of low-temperature sputtered AlN layer which is compatible with the manufacturing of Si integrated circuits.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"103 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139810340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improved light extraction efficiency of AlGaN DUV light emitting diodes using Al/MgF2-based highly reflective film 使用基于 Al/MgF2 的高反射膜提高 AlGaN DUV 发光二极管的光提取效率

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad255a

Peishan Li, Xiaoyue Huang, Yuqing Yang, Zhenghao Xia, Qiao Wang, Hang Chen, Xingfu Wang

{"title":"Improved light extraction efficiency of AlGaN DUV light emitting diodes using Al/MgF2-based highly reflective film","authors":"Peishan Li, Xiaoyue Huang, Yuqing Yang, Zhenghao Xia, Qiao Wang, Hang Chen, Xingfu Wang","doi":"10.1088/1361-6641/ad255a","DOIUrl":"https://doi.org/10.1088/1361-6641/ad255a","url":null,"abstract":"\u0000 AlGaN DUV light emitting diodes (DUV-LEDs) (275 nm emission) are safe, eco-friendly and smart alternatives for inactivating viruses and bacteria. However, DUV-LEDs suffer from the main bottleneck of low external quantum efficiencies, which are strongly associated with the low light extraction efficiency caused by the strong optical polarisation of Al-rich AlGaN. Optical simulation results show that the luminous intensity of DUV-LEDs was increased by 10% owing to the synergistic effect of the sidewalls and substrates. The optical power of DUV-LEDs was increased to 16.8%, the far-field pattern was expanded to 130 degrees and the emission intensity was more focus on the central region, proving that the highly reflective sidewalls and substrates could re-direct the sideways-travelling photons for extraction. Moreover, we also investigated the reflective mechanism of Al/MgF2 layers. Optimise refractive index distribution of Al/MgF2 layers could change the electric field intensity to improve the reflectivity. Meanwhile, the temperature of the sample after coating were significantly reduced by 7.33%. Thermal radiation benefits and the high stability of bonding interface are the main reasons to reduce the temperature of DUVLEDs after Al/MgF2 coating. The present strategy is proposed from the view of the chip fabrication, which is cost-effective, able to be manufactured at a large scale.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"18 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139870362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Franz‐Keldysh effect in the optical absorption spectrum of TlGaSe2 layered semiconductor caused by charged native defects 带电原生缺陷导致 TlGaSe2 层状半导体光吸收光谱中的弗朗兹-凯尔迪什效应

Semiconductor Science and Technology Pub Date : 2024-02-02 DOI: 10.1088/1361-6641/ad255b

Serdar Gören, Yasin Şale, MirHasan Yunus Seyidov

{"title":"The Franz‐Keldysh effect in the optical absorption spectrum of TlGaSe2 layered semiconductor caused by charged native defects","authors":"Serdar Gören, Yasin Şale, MirHasan Yunus Seyidov","doi":"10.1088/1361-6641/ad255b","DOIUrl":"https://doi.org/10.1088/1361-6641/ad255b","url":null,"abstract":"\u0000 The Franz-Keldysh effect in the optical absorption edge of bulk TlGaSe2 layered semiconductor poled under an external electric field was investigated in the present work. The Franz-Keldysh shift below the optical band gap absorption region, as well as the quasi-periodic oscillations above the fundamental band gap of TlGaSe2, were observed. The measured changes in optical light absorption of the TlGaSe2 sample were revealed after poling processing. The poling technique is used to produce the built-in internal electric field within the TlGaSe2 semiconductor. The frozen-in internal electric field in TlGaSe2 was experimentally monitored through changes in the line–shape of the absorption spectra at the fundamental band edge. The observed results are accurately fitted with the theoretical line-shape function of the Franz - Keldysh absorption tail below the bandgap of TlGaSe2 and quasi-periodic oscillations above the bandgap. A good agreement between theoretical and experimental results took place. The present study demonstrated that the Franz - Keldysh effect can be used to identify and characterize the localized internal electric fields originating from the electrically active native imperfections in the TlGaSe2 crystals.","PeriodicalId":507064,"journal":{"name":"Semiconductor Science and Technology","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139811544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0