Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930447
Atse Julien Eric N'Dohi, C. Sonneville, Soufiane Saidi, T. Ngo, P. de Mierry, É. Frayssinet, Y. Cordier, L. Phung, F. Morancho, K. Isoird, J. Tasselli, H. Maher, D. Planson
In this work, measurements from cathodo-luminescence (CL), micro-Raman spectroscopy and current-voltage I (V) have been coupled to assess the effects of physical parameters such as threading dislocations and effective doping level homogeneity on the electrical performances of vertical GaN Schottky diodes.
{"title":"Multiphysics Characterizations of Vertical GaN Schottky Diodes","authors":"Atse Julien Eric N'Dohi, C. Sonneville, Soufiane Saidi, T. Ngo, P. de Mierry, É. Frayssinet, Y. Cordier, L. Phung, F. Morancho, K. Isoird, J. Tasselli, H. Maher, D. Planson","doi":"10.1109/CSW55288.2022.9930447","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930447","url":null,"abstract":"In this work, measurements from cathodo-luminescence (CL), micro-Raman spectroscopy and current-voltage I (V) have been coupled to assess the effects of physical parameters such as threading dislocations and effective doping level homogeneity on the electrical performances of vertical GaN Schottky diodes.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126394277","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930376
M. Benjelloun, Nedal Al Taradeh, C. Rodriguez, N. Gogneau, A. Soltani, D. Morris, J. Harmand, H. Maher
A novel enhanced vertical GaN nanowire transistor structure is designed and optimized using the TCAD tool. The impact of the diameter, length, and doping concentration has been analyzed for the channel and drift region parts with and without surface traps. For the channel region, it has been observed that the device is Normally-OFF when the nanowire’s diameter and channel doping are less than 200 nm and 1×1017 cm−3, respectively. When considering a density of acceptor-type surface traps of 1×1013 cm−2.eV−1, the threshold voltage (Vth) has slightly increased. The breakdown voltage (VBR) of the device is found to increase as the length of the drift region increases and as the diameter of the nanowire decreases. Our simulation results show that the on-state resistance (RON) of the device increases drastically at low doping level of the drift region, when surface traps are taken into account. The threshold value of the doping level, above which RON remains small and insensitive to surface traps, increases as the nanowire diameter decreases.
{"title":"Design and Optimization of New Enhanced Vertical GaN Nanowire Transistor Using Sentaurus TCAD for Power Applications","authors":"M. Benjelloun, Nedal Al Taradeh, C. Rodriguez, N. Gogneau, A. Soltani, D. Morris, J. Harmand, H. Maher","doi":"10.1109/CSW55288.2022.9930376","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930376","url":null,"abstract":"A novel enhanced vertical GaN nanowire transistor structure is designed and optimized using the TCAD tool. The impact of the diameter, length, and doping concentration has been analyzed for the channel and drift region parts with and without surface traps. For the channel region, it has been observed that the device is Normally-OFF when the nanowire’s diameter and channel doping are less than 200 nm and 1×1017 cm−3, respectively. When considering a density of acceptor-type surface traps of 1×1013 cm−2.eV−1, the threshold voltage (Vth) has slightly increased. The breakdown voltage (VBR) of the device is found to increase as the length of the drift region increases and as the diameter of the nanowire decreases. Our simulation results show that the on-state resistance (RON) of the device increases drastically at low doping level of the drift region, when surface traps are taken into account. The threshold value of the doping level, above which RON remains small and insensitive to surface traps, increases as the nanowire diameter decreases.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126438976","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930457
A. Papamichail, Axel R. Persson, Steffen Ricther, P. Kühne, P. O. Persson, M. Thorsell, H. Hjelmgren, N. Rorsman, V. Darakchieva
Although AlGaN/GaN HEMTs with high power and current gain have been demonstrated in RF device applications, at high signal operation they show an inherent non-linear behavior which leads to gain compression and signal distortion. Polarization-doped AlGaN/GaN HEMTs, with a compositionally graded channel enables a linear response improvement through formation of a 3-D electron gas. In this work, we develop the growth process for graded channel HEMTs in a hot-wall MOCVD reactor. Control of the grading profile is established through growth parameter tuning. Afterwards, analysis by EDS allows for precise determination of Al composition across the channel. Conventional and graded channel HEMT structures were fabricated and characterized. Furthermore, the sheet resistance, carrier density and mobility in HEMT structures with different grading profiles are compared and discussed. The conventional (non-graded) structure revealed the highest electron mobility of ~2350 cm2/V.s, which is among the highest values reported.
{"title":"Compositionally graded channel HEMTs towards improved linearity for low-noise RF amplifiers","authors":"A. Papamichail, Axel R. Persson, Steffen Ricther, P. Kühne, P. O. Persson, M. Thorsell, H. Hjelmgren, N. Rorsman, V. Darakchieva","doi":"10.1109/CSW55288.2022.9930457","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930457","url":null,"abstract":"Although AlGaN/GaN HEMTs with high power and current gain have been demonstrated in RF device applications, at high signal operation they show an inherent non-linear behavior which leads to gain compression and signal distortion. Polarization-doped AlGaN/GaN HEMTs, with a compositionally graded channel enables a linear response improvement through formation of a 3-D electron gas. In this work, we develop the growth process for graded channel HEMTs in a hot-wall MOCVD reactor. Control of the grading profile is established through growth parameter tuning. Afterwards, analysis by EDS allows for precise determination of Al composition across the channel. Conventional and graded channel HEMT structures were fabricated and characterized. Furthermore, the sheet resistance, carrier density and mobility in HEMT structures with different grading profiles are compared and discussed. The conventional (non-graded) structure revealed the highest electron mobility of ~2350 cm2/V.s, which is among the highest values reported.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126168706","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930416
J. Lee, Y. Tsai, C. Bayram
Cubic GaN is a promising platform for realizing high-efficiency green light emitting diodes, suitable for closing the green gap and enabling color-mixed solid-state lighting applications. Still, there are almost no studies on such LEDs and none showing how cubic GaN LED design rules compare to or differentiate against conventional hexagonal and nonpolar ones. Here, using the Open Boundary Quantum LED Simulator, we present design guidelines for highly efficient cubic green LEDs and detail the inherent advantages and design differences between polar, nonpolar, and cubic GaN LEDs.
{"title":"Green Light Emitting Diodes for the Ultimate Solid-State Lighting","authors":"J. Lee, Y. Tsai, C. Bayram","doi":"10.1109/CSW55288.2022.9930416","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930416","url":null,"abstract":"Cubic GaN is a promising platform for realizing high-efficiency green light emitting diodes, suitable for closing the green gap and enabling color-mixed solid-state lighting applications. Still, there are almost no studies on such LEDs and none showing how cubic GaN LED design rules compare to or differentiate against conventional hexagonal and nonpolar ones. Here, using the Open Boundary Quantum LED Simulator, we present design guidelines for highly efficient cubic green LEDs and detail the inherent advantages and design differences between polar, nonpolar, and cubic GaN LEDs.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130260354","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930357
Bei Shi, Si Zhu, B. Song, J. Klamkin
InGaAs/GaAs multi-quantum wells were selectively grown on flat-bottom (001) silicon recesses and their efficiencies were improved by introducing GaAsP strain compensation layers. Room-temperature lasing from microdisks were subsequently fabricated and yield low lasing threshold.
{"title":"Growth Optimization of InGaAs/GaAs Multi Quantum Well Microdisk Lasers on Flat-bottom CMOS-compatible (001) Si by Selective Area Heteroepitaxy","authors":"Bei Shi, Si Zhu, B. Song, J. Klamkin","doi":"10.1109/CSW55288.2022.9930357","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930357","url":null,"abstract":"InGaAs/GaAs multi-quantum wells were selectively grown on flat-bottom (001) silicon recesses and their efficiencies were improved by introducing GaAsP strain compensation layers. Room-temperature lasing from microdisks were subsequently fabricated and yield low lasing threshold.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127124237","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930421
F. F. Ince, A. T. Newell, K. Reilly, S. Seth, T. Rotter, A. Mansoori, D. Shima, P. Webster, E. Vaughan, G. Balakrishnan
Interfacial misfit dislocation growth (IMF) mode can be used to achieve spontaneous and fully relaxed GaSb on GaAs however a high residual threading dislocation density of ~ 108 dislocations/cm2 is present. In this paper, we demonstrate a method to decrease the threading dislocation density using defect filtering layers with different filter designs. Moreover, we show the comparison of mobility of n and p pseudomorphic channels grown on these structures with and without using defect filtering layers.
{"title":"Techniques for reduction of threading dislocations in metamorphic growth of GaSb on GaAs for realization of high mobility n and p channels","authors":"F. F. Ince, A. T. Newell, K. Reilly, S. Seth, T. Rotter, A. Mansoori, D. Shima, P. Webster, E. Vaughan, G. Balakrishnan","doi":"10.1109/CSW55288.2022.9930421","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930421","url":null,"abstract":"Interfacial misfit dislocation growth (IMF) mode can be used to achieve spontaneous and fully relaxed GaSb on GaAs however a high residual threading dislocation density of ~ 108 dislocations/cm2 is present. In this paper, we demonstrate a method to decrease the threading dislocation density using defect filtering layers with different filter designs. Moreover, we show the comparison of mobility of n and p pseudomorphic channels grown on these structures with and without using defect filtering layers.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"107 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114150789","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930389
N. Sepelak, Jeremiah D. Williams, D. Dryden, Rachel Kahler, K. Liddy, Weisong Wang, K. Chabak, A. Green, A. Islam
β-Ga2O3 offers a robust platform for operation of electronic devices at high temperature and in extreme environments due to its large band gap of ~4.8 eV and low intrinsic carrier concentration. In this study, we characterize β-Ga2O3 field effect transistors from room temperature (RT) up to 500 °C. The devices, fabricated with Ni/Au gate metal and Al2O3 gate dielectric, exhibited stable operation up to 500 °C. The measured ID-VD characteristics showed no current degradation up to 450 °C; in fact, current improved in this temperature range due to activation carriers from dopants/traps in the device. At 500 °C, device exhibited a drop in ID; however, device characteristics are recovered once the device is brought back to RT even after 20 hours of device operation at 500 °C. All other device characteristics (gate leakage, ION/IOFF ratio, gm, Ron, contact resistance) showed monotonic variation with temperature, which has been explained using appropriate device physics and by considering the interaction of gate metals with Al2O3. Our results suggest that with appropriate choice of metals and gate dielectrics the 500 °C operation using β-Ga2O3 has no bottlenecks.
{"title":"First Demonstration of 500 °C Operation of β-Ga2O3 MOSFET in Air","authors":"N. Sepelak, Jeremiah D. Williams, D. Dryden, Rachel Kahler, K. Liddy, Weisong Wang, K. Chabak, A. Green, A. Islam","doi":"10.1109/CSW55288.2022.9930389","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930389","url":null,"abstract":"β-Ga<inf>2</inf>O<inf>3</inf> offers a robust platform for operation of electronic devices at high temperature and in extreme environments due to its large band gap of ~4.8 eV and low intrinsic carrier concentration. In this study, we characterize β-Ga<inf>2</inf>O<inf>3</inf> field effect transistors from room temperature (RT) up to 500 °C. The devices, fabricated with Ni/Au gate metal and Al<inf>2</inf>O<inf>3</inf> gate dielectric, exhibited stable operation up to 500 °C. The measured I<inf>D</inf>-V<inf>D</inf> characteristics showed no current degradation up to 450 °C; in fact, current improved in this temperature range due to activation carriers from dopants/traps in the device. At 500 °C, device exhibited a drop in I<inf>D</inf>; however, device characteristics are recovered once the device is brought back to RT even after 20 hours of device operation at 500 °C. All other device characteristics (gate leakage, I<inf>ON</inf>/I<inf>OFF</inf> ratio, g<inf>m</inf>, R<inf>on</inf>, contact resistance) showed monotonic variation with temperature, which has been explained using appropriate device physics and by considering the interaction of gate metals with Al<inf>2</inf>O<inf>3</inf>. Our results suggest that with appropriate choice of metals and gate dielectrics the 500 °C operation using β-Ga<inf>2</inf>O<inf>3</inf> has no bottlenecks.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122319955","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}
Pub Date : 2022-06-01DOI: 10.1109/csw55288.2022.9930348
Hnin Lai Lai Aye, K. Hayashi, Haruki Orito, B. Lin, Ikuya Suzuki, B. Ma, Y. Ishitani
Longitudinal optical (LO) phonon resonant THz absorption and radiation subjected to metal-semiconductor surface stripe structures are observed due to oscillation of interface polarization charges. The radiation intensity is affected by the stripe structural characteristics accompanying independent LO peak positioned at 8.5THz. LO phonon scattering rate is more evident in wide and high mesa-height semiconductor stripes in which absorption efficiency is affected rather than narrower ones.
{"title":"Structure Dependent Characteristics of Infrared Radiation from Metal-Semiconductor Surface Micro-Structures","authors":"Hnin Lai Lai Aye, K. Hayashi, Haruki Orito, B. Lin, Ikuya Suzuki, B. Ma, Y. Ishitani","doi":"10.1109/csw55288.2022.9930348","DOIUrl":"https://doi.org/10.1109/csw55288.2022.9930348","url":null,"abstract":"Longitudinal optical (LO) phonon resonant THz absorption and radiation subjected to metal-semiconductor surface stripe structures are observed due to oscillation of interface polarization charges. The radiation intensity is affected by the stripe structural characteristics accompanying independent LO peak positioned at 8.5THz. LO phonon scattering rate is more evident in wide and high mesa-height semiconductor stripes in which absorption efficiency is affected rather than narrower ones.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"255 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133428337","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930451
R. Günkel, J. Glowatzki, S. Patil, O. Maßmeyer, S. Chatterjee, A. Beyer, W. Stolz, K. Volz
Two-dimensional (2D) layered III–VI semiconductor crystals were grown on c-plane sapphire by MOCVD. A growth scheme for monolayered InxSey was found. By optimizing the growth parameters such as temperature and Se to In ratio, the growth behaviour changes from a vapor liquid solid growth mode to a layer by layer growth mode. Due to these encouraging achievements, further progress leading to the deposition of 2D materials over large areas is expected.
利用MOCVD技术在c面蓝宝石表面生长出二维(2D)层状III-VI半导体晶体。找到了一种单层InxSey的生长方案。通过优化生长参数如温度和Se to In比，使生长行为由气液固生长模式转变为逐层生长模式。由于这些令人鼓舞的成就，进一步的进展导致大面积的二维材料沉积有望实现。
{"title":"MOCVD Growth of InxSey Monolayers","authors":"R. Günkel, J. Glowatzki, S. Patil, O. Maßmeyer, S. Chatterjee, A. Beyer, W. Stolz, K. Volz","doi":"10.1109/CSW55288.2022.9930451","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930451","url":null,"abstract":"Two-dimensional (2D) layered III–VI semiconductor crystals were grown on c-plane sapphire by MOCVD. A growth scheme for monolayered InxSey was found. By optimizing the growth parameters such as temperature and Se to In ratio, the growth behaviour changes from a vapor liquid solid growth mode to a layer by layer growth mode. Due to these encouraging achievements, further progress leading to the deposition of 2D materials over large areas is expected.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125097862","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}
Pub Date : 2022-06-01DOI: 10.1109/CSW55288.2022.9930448
Kailing Pan, Huaxing Jiang, W. Tang, K. Lau
This paper reports the suppression of current collapse in Al2O3/AlGaN/GaN MOSHEMTs on Si with sub-bandgap light illumination. Both the gate pulsed IDS-VGS and double pulsed IDS-VDS characteristics under 405-nm light illumination reveal that the sub-bandgap light illumination can effectively mitigate the electron trapping effect in the gate stack, thereby reducing the current collapse, despite a potential cost of increased off-state leakage current.
{"title":"Current Collapse Reduction in Al2O3/AlGaN/GaN MOSHEMTs on Si with Sub-bandgap Light Illumination","authors":"Kailing Pan, Huaxing Jiang, W. Tang, K. Lau","doi":"10.1109/CSW55288.2022.9930448","DOIUrl":"https://doi.org/10.1109/CSW55288.2022.9930448","url":null,"abstract":"This paper reports the suppression of current collapse in Al<inf>2</inf>O<inf>3</inf>/AlGaN/GaN MOSHEMTs on Si with sub-bandgap light illumination. Both the gate pulsed I<inf>DS</inf>-V<inf>GS</inf> and double pulsed I<inf>DS</inf>-V<inf>DS</inf> characteristics under 405-nm light illumination reveal that the sub-bandgap light illumination can effectively mitigate the electron trapping effect in the gate stack, thereby reducing the current collapse, despite a potential cost of increased off-state leakage current.","PeriodicalId":382443,"journal":{"name":"2022 Compound Semiconductor Week (CSW)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123120696","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：