{"title":"Fast β-Ga₂O₃ Solar-Blind Photodetectors With High Detectivity on Sapphire Substrates","authors":"Chen He;Jun Zheng;Yiyang Wu;Jinlai Cui;Xiangquan Liu;Zhi Liu;Yuhua Zuo;Buwen Cheng","doi":"10.1109/LED.2024.3497005","DOIUrl":"https://doi.org/10.1109/LED.2024.3497005","url":null,"abstract":"Ga2O3 Solar blind photodetectors (PDs) have been widely researched in recent years due to their ultrawide bandgap. In this work, high-quality \u0000<inline-formula> <tex-math>$beta $ </tex-math></inline-formula>\u0000-Ga2O3 film with Full Width at Half Maximum (FWHM) of 0.19° was grown on sapphire substrates by MOCVD. The Ga2O3 Metal Semiconductor-Metal PDs were fabricated, showing a high response wavelength selectivity of \u0000<inline-formula> <tex-math>${1.89} times {10} ^{{5}}$ </tex-math></inline-formula>\u0000 (R\u0000<inline-formula> <tex-math>$_{text {250 nm}}$ </tex-math></inline-formula>\u0000/R\u0000<inline-formula> <tex-math>$_{text {400 nm}})$ </tex-math></inline-formula>\u0000. At 10 V, the PDs show responsivity (R) of about 500 A/W at 254 nm, specific detectivity (D*) of \u0000<inline-formula> <tex-math>$1.7times 10^{{14}}$ </tex-math></inline-formula>\u0000 Jones, and response time of merely 1.5 ms, indicating its great potential for solar blind detection. Finally, images became unclear under illuminated light of about 178 nW/cm2 at 254 nm wavelength. These results open avenues for advanced Ga2O3-based optoelectronics.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"56-59"},"PeriodicalIF":4.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuxiang Lin;Siyu Tong;Jiaqi Niu;Runze Li;Qunfeng Niu;Peng Li;Li Wang;Shujing Lin
{"title":"Foam-Structured Strain Sensor-Based Elastic Wearable System for Pulse Wave Detection","authors":"Shuxiang Lin;Siyu Tong;Jiaqi Niu;Runze Li;Qunfeng Niu;Peng Li;Li Wang;Shujing Lin","doi":"10.1109/LED.2024.3496859","DOIUrl":"https://doi.org/10.1109/LED.2024.3496859","url":null,"abstract":"Timely detection of abnormal pulse wave conditions can provide early warnings for cardiovascular emergencies. Strain sensors can detect subtle pulse wave changes, however, they often face a trade-off between flexibility and accuracy. Herein, we present a cost-effective, high-sensitivity elastic strain sensor based on foam-structured silicone rubber@nanocarbon black (SR@CB). The sensor exhibits excellent linearity within a strain range of 0-60%, with a detection sensitivity of 0.1% and a gauge factor of up to 32. Thus, it can detect not only subtle pulse wave signals, but also be used for motion monitoring. Moreover, we have developed an elastic circuit detection system prototype, significantly enhancing wearer comfort while achieving a fully elastic detection system. We foresee this fully elastic detection system holds promise for health monitoring and motion detection applications.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"111-114"},"PeriodicalIF":4.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142905860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Low Contact Resistivity of <10 Ω·mm for Au-Free Ohmic Contact on p-GaN/AlGaN/GaN","authors":"ChuYing Tang;ChengKai Deng;Chun Fu;Jiaqi He;Fangzhou Du;Peiran Wang;Kangyao Wen;Yi Zhang;Yang Jiang;Nick Tao;Wenyue Yu;Qing Wang;HongYu Yu","doi":"10.1109/LED.2024.3497584","DOIUrl":"https://doi.org/10.1109/LED.2024.3497584","url":null,"abstract":"A robust Au-free p-type ohmic contact process with ultralow contact resistivity is developed on p-GaN/AlGaN/GaN, which demonstrates the potential of GaN CMOS to be compatible with Si CMOS process lines. A novel metal stack of Mg/Ni/Pt is designed, and ultralow contact resistivity of \u0000<inline-formula> <tex-math>$8 ; Omega cdot $ </tex-math></inline-formula>\u0000mm (\u0000<inline-formula> <tex-math>${1}.{0} times {10}^{-{5}} ; Omega cdot $ </tex-math></inline-formula>\u0000cm\u0000<inline-formula> <tex-math>$^{{2}}text {)}$ </tex-math></inline-formula>\u0000 is achieved. It is revealed that the Ga vacancies on the p-GaN surface induced by Ni, and the Ni2O3 embed in the decomposed p-GaN are key to forming stable low resistivity ohmic contact.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"24-27"},"PeriodicalIF":4.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved Wavelength Stability of InGaN-Based Red LEDs Grown on Graphene/SiC Substrates","authors":"Jiaqi Yu;Gaoqiang Deng;Yunfei Niu;Yusen Wang;Haotian Ma;Shixu Yang;Changcai Zuo;Jingkai Zhao;Haozhe Gao;Guoxing Li;Baolin Zhang;Yuantao Zhang","doi":"10.1109/LED.2024.3496940","DOIUrl":"https://doi.org/10.1109/LED.2024.3496940","url":null,"abstract":"The application of InGaN based red LEDs in Micro LED display has been severely limited due to their low luminous efficiency and poor wavelength stability. In this work, we demonstrate InGaN based red LEDs with improved wavelength stability on SiC substrates. The key of our method is to introduce a graphene intermediate layer between the epitaxial LED structure and SiC substrate. Another important process is to modulate the growth behavior and stress state of the GaN film and LED structure on graphene. This is achieved by optimizing the nitrogen-plasma pre-treatment time of graphene. As a consequence, InGaN based red LEDs with small wavelength shift with the change of driving current are obtained. The wavelength shift is 8 nm as the forward driving current density increase from 1 to 10 A/cm2, which is significantly lower than the 25 nm of the reference red LEDs directly grown on SiC substrates. In addition, we analyse the mechanism responds to the improvements of wavelength stability for the red LEDs grown on graphene/SiC. This work provides a feasible approach for enhancing the wavelength stability of InGaN based red LEDs.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"72-75"},"PeriodicalIF":4.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Suppressing the Dark Current of PbS QD SWIR Photodetector by Freeze-Treated Hole Transport Layer","authors":"Fan Fang;Weichao Wang;Yiwen Li;Xiao Wang;Lihai Xu;Simin Chen;Tao Cao;Haibo Zhu;Lei Rao;Kaiyu Luo;Jun Tang;Yulong Chen;Junjie Hao;Wei Chen;Haodong Tang","doi":"10.1109/LED.2024.3496412","DOIUrl":"https://doi.org/10.1109/LED.2024.3496412","url":null,"abstract":"Lead sulfide (PbS) quantum dot (QD) photodetector is considered as a key component of the next-generation infrared machine vision applications for its wide detection range and effective fabrication cost. Leakage current caused by film cracks and trap states during the film fabrication stops the further optimization of device performance and slows down the industrialization of the PbS QD photodetector. An optimized hole transport layer based on PbS QD with minimized cracks and trap states is achieved through a freeze-centrifugation purification before the ligand-exchange process, leading to a suppressed dark current density (260 nA/cm\u0000<inline-formula> <tex-math>$^{{2}}text {)}$ </tex-math></inline-formula>\u0000, strongly reduced noise current (26 fA/Hz\u0000<inline-formula> <tex-math>$^{{1}{/{2}}}text {)}$ </tex-math></inline-formula>\u0000. Enhanced film quality brings an ultra-high detectivity (\u0000<inline-formula> <tex-math>${5}.{47}times {10} ^{{12}}$ </tex-math></inline-formula>\u0000Jones) and faster response-time (\u0000<inline-formula> <tex-math>$1.4mu$ </tex-math></inline-formula>\u0000s) of the freeze-treated photodetector under zero bias.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"52-55"},"PeriodicalIF":4.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High-Speed and High-Responsivity Quasi- Vertical Schottky Photodetectors of Epitaxial Ga 2O 3on Pt Substrate","authors":"Huanyu Zhang;Chunhong Zeng;Tiwei Chen;Li Zhang;Gaofu Guo;Zhucheng Li;Yu Hu;Zhili Zou;Xiaodong Zhang;Wenhua Shi;Zhongming Zeng;Baoshun Zhang","doi":"10.1109/LED.2024.3496557","DOIUrl":"https://doi.org/10.1109/LED.2024.3496557","url":null,"abstract":"A quasi-vertical Schottky diodes with high speed and high responsivity were demonstrated by epitaxially growing Ga 2O 3on Pt. The research further investigated the impact of incorporating metal stripes in the photosensitive region to enhance both the responsivity and response speed of the device. Characterization of the photoresponses reveals that these devices exhibit high sensitivity to solar-blind ultraviolet light, peaking at approximately 260 nm. At the bias of −5V, the detector achieves a responsivity of 2998 A/W, an exceptional specific detectivity of \u0000<inline-formula> <tex-math>$1.68times 10^{{7}}$ </tex-math></inline-formula>\u0000 Jones and a high response speed about 0.1 ms. By applying these metrics demonstrate substantial improvements over existing technologies and suggest a promising avenue for developing high speed and high responsivity photodetectors.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"60-63"},"PeriodicalIF":4.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bukun Xu;Yazi Cao;Shichang Chen;Bo Yuan;Gaofeng Wang
{"title":"Compact On-Chip Cul-De-Sac Mixed Topology Bandpass Filter With Extracted-Pole Unit Using TGV Technology","authors":"Bukun Xu;Yazi Cao;Shichang Chen;Bo Yuan;Gaofeng Wang","doi":"10.1109/LED.2024.3496444","DOIUrl":"https://doi.org/10.1109/LED.2024.3496444","url":null,"abstract":"A compact on-chip mixed topology bandpass filter (BPF) is proposed. By virtue of a new cul-de-sac structure, this BPF realizes transmission zeros (TZs) in pairs at both high and low frequency ends simultaneously. An extracted-pole unit, which can generate two additional TZs outside the passband of the BPF, is also employed. The presence of multiple TZs can greatly improve the outband rejection performance. The proposed topology is realized using laser-induced wet etching through glass via (TGV) technology, which has merits of high precision, ease integration, and process simplification. In particular, the proposed topology can effectively reduce the filter area by 24%. The use of Metal-Insulator-Metal (MIM) capacitors and spiral inductors further reduces its size. A fabricated prototype shows the minimum in-band insertion loss is 2.49 dB and the 3-dB fractional bandwidth is 25.3%. The BPF size is 1.6 mm \u0000<inline-formula> <tex-math>$times 0.8$ </tex-math></inline-formula>\u0000 mm \u0000<inline-formula> <tex-math>$times 0.35$ </tex-math></inline-formula>\u0000 mm, which is only about \u0000<inline-formula> <tex-math>$0.0131~lambda _{{0}} times 0.0065~lambda _{{0}}$ </tex-math></inline-formula>\u0000 at \u0000<inline-formula> <tex-math>${f}_{{0}} =2.45$ </tex-math></inline-formula>\u0000 GHz.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"8-11"},"PeriodicalIF":4.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unveiling the Role of Local Stress in Enhancing Ferroelectric Properties and Endurance of HfO₂/ZrO₂ Superlattice Structures","authors":"Boyao Cui;Sheng Ye;Xuepei Wang;Maokun Wu;Yuchun Li;Yishan Wu;Yichen Wen;Jinhao Liu;Xiaoxi Li;Pengpeng Ren;Zhigang Ji;Hongliang Lu;David Wei Zhang;Runsheng Wang;Ru Huang","doi":"10.1109/LED.2024.3496720","DOIUrl":"https://doi.org/10.1109/LED.2024.3496720","url":null,"abstract":"Ferroelectric superlattices (SL) composed of HfO2 and ZrO2 have garnered significant interest due to their outstanding performance. In this letter, we revealed that the SL structure facilitates ferroelectric excitation by introducing local stress compared to solid solution (SS) HZO. This additional stress results in an earlier saturation of polarization during annealing process and thus less annealing time is needed for SL. The thermal defects (e.g. oxygen vacancy) are effectively mitigated, leading to a remarkable improvement in endurance simultaneously. The precise modulation of local stress achieved through stack engineering unlocks vast potential for ferroelectric devices, enabling them to exhibit superior ferroelectricity and unprecedented reliability.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"107-110"},"PeriodicalIF":4.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142905861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kang’an Jiang;Su Hu;Zhiyan Zheng;Zhuyikang Zhao;Dehui Huang;Shuai Liu;Heyu Shen;Hui Wang
{"title":"Large Lateral Photovoltaic Effect and Spatial Resistance Effect on MoS₂/p-Si Interface","authors":"Kang’an Jiang;Su Hu;Zhiyan Zheng;Zhuyikang Zhao;Dehui Huang;Shuai Liu;Heyu Shen;Hui Wang","doi":"10.1109/LED.2024.3495674","DOIUrl":"https://doi.org/10.1109/LED.2024.3495674","url":null,"abstract":"An in-depth study of new phenomena emerging from the interaction between light and matter is a vital scientific research effort. In this report, we investigate the lateral photovoltaics and spatial resistance on p-Si surfaces under 520 nm laser stimulation. Because of the surface states of p-Si, the lateral photovoltage sensitivity can reach 286 mV/mm, and the spatial resistance change ratio can reach 1059%. Then, we modulate these two effects by growing three different morphologies of MoS2 on the Si surface. Due to the photosensitive properties of MoS2 nanoparticles, the lateral photovoltage sensitivity can be enhanced up to 368 mV/mm, while the spatial resistance change ratio can reach 2202%. In this process, we observe a new phenomenon that the p-Si surface modified by MoS2 no longer shows the traditional bipolar-resistance effect, and the laser position corresponding to the minimum resistance has been shifted. Based on this finding, we refine the previously proposed bipolar-resistance effect theory and confirm our findings through theoretical calculations. Our modulation strategy can realize both photovoltage-based detection and photoconductivity-based detection, which provides a reliable reference for the study of photoelectric devices.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"20-23"},"PeriodicalIF":4.1,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Demonstration of a Four-Beam Integrated Travelling Wave Tube in W-Band","authors":"Huanli Ji;Jinsheng Yang;Ran Sun;Hanshuo Mu;Jun Cai;Pan Pan;Jinjun Feng","doi":"10.1109/LED.2024.3495678","DOIUrl":"https://doi.org/10.1109/LED.2024.3495678","url":null,"abstract":"This letter presents an investigation into a W-band four-beam planar-integrated traveling wave tube (TWT). Building on the design concept of the planar integrated TWT, this research focuses on the high-efficiency circuit that utilizes a bending FWG, verified through the fabrication of a tube employing a conventional PPM system. Further research on the four-beam TWT utilizing the proposed planar integrated periodic permanent magnet (PIPPM) led to its development, assembly, and testing. Experiment results achieved over 85% transmission efficiency through a 120 mm long tunnel, validating this beam optical system configuration. The device attained a maximum saturated output power of 10 W and a saturated gain of 23 dB, with a bandwidth of 6 GHz per channel at an operating voltage of 12.6 kV. The four-beam TWT demonstrates consistent electrical performance and offers a novel solution for short-wavelength millimeter-wave TWT active phased arrays applications.","PeriodicalId":13198,"journal":{"name":"IEEE Electron Device Letters","volume":"46 1","pages":"96-99"},"PeriodicalIF":4.1,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142905836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}