Pub Date : 2026-01-22DOI: 10.1016/j.vacuum.2026.115106
E. Ermakova , A. Plehanov , A. Saraev , E. Gerasimov , V. Shayapov , E. Maksimovskiy , V. Sulyaeva , A. Kolodin , M. Kosinova
Hydrogenated silicon carbonitride (SiCxNy:H) films have received much attention for applications in microelectronics, particularly as interlayer dielectrics and copper diffusion barriers. However, the demonstrated properties are crucially dependent on the elemental composition and chemical bonding structure. Thus, precise control over the type of precursors and deposition conditions is necessary for the development of efficient experimental procedure. In this study, SiCxNy:H films were deposited at 200–450 °C by plasma-enhanced chemical vapor deposition (PECVD) using hexamethyldisilane (HMDS, Me3Si–SiMe3) in mixtures with nitrogen or ammonia, as well as hexamethyldisilazane (HMDSN, Me3Si–NH–SiMe3) with helium. The motivation is to establish a fundamental correlation between the plasma chemistry, driven by different nitrogen sources (N2, NH3, or the amine group in HMDSN), and film properties. Under low-power conditions the three distinct series of non-porous materials, characterized as Si–C-type and two Si–N-type, were obtained. Refractive index and dielectric constant changed in the range of 1.62–1.99 and 3.8–5.4, respectively, were related to the deposition conditions and chemical composition of the films. Transmittance electron microscopy (TEM) investigation showed the films are suitable as diffusion barriers for Cu/low-k damascene integration.
{"title":"Amorphous SiCxNy:H thin films produced with various nitrogen sources: A comparative study","authors":"E. Ermakova , A. Plehanov , A. Saraev , E. Gerasimov , V. Shayapov , E. Maksimovskiy , V. Sulyaeva , A. Kolodin , M. Kosinova","doi":"10.1016/j.vacuum.2026.115106","DOIUrl":"10.1016/j.vacuum.2026.115106","url":null,"abstract":"<div><div>Hydrogenated silicon carbonitride (SiC<sub>x</sub>N<sub>y</sub>:H) films have received much attention for applications in microelectronics, particularly as interlayer dielectrics and copper diffusion barriers. However, the demonstrated properties are crucially dependent on the elemental composition and chemical bonding structure. Thus, precise control over the type of precursors and deposition conditions is necessary for the development of efficient experimental procedure. In this study, SiC<sub>x</sub>N<sub>y</sub>:H films were deposited at 200–450 °C by plasma-enhanced chemical vapor deposition (PECVD) using hexamethyldisilane (HMDS, Me<sub>3</sub>Si–SiMe<sub>3</sub>) in mixtures with nitrogen or ammonia, as well as hexamethyldisilazane (HMDSN, Me<sub>3</sub>Si–NH–SiMe<sub>3</sub>) with helium. The motivation is to establish a fundamental correlation between the plasma chemistry, driven by different nitrogen sources (N<sub>2</sub>, NH<sub>3</sub>, or the amine group in HMDSN), and film properties. Under low-power conditions the three distinct series of non-porous materials, characterized as Si–C-type and two Si–N-type, were obtained. Refractive index and dielectric constant changed in the range of 1.62–1.99 and 3.8–5.4, respectively, were related to the deposition conditions and chemical composition of the films. Transmittance electron microscopy (TEM) investigation showed the films are suitable as diffusion barriers for Cu/low-k damascene integration.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115106"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-22DOI: 10.1016/j.vacuum.2026.115132
G. Yu Yushkov, V.D. Gridilev, A.G. Nikolaev, E.M. Oks
We present the results of our experiments of specific erosion of 13 different cathode materials in a microsecond pulsed vacuum arc with current 200 A. The specific erosion of materials with relatively high melting points, greater than Тmelt = 650 °C for magnesium, was found to lie within the range from 30 to 100 μg/C, which is typical of erosion in vacuum arc cathode spots. For materials with low melting points, below Тmelt = 328 °C for lead, anomalously high specific erosion in the range from 500 to 1000 μg/C was observed. We find that this high erosion is due to the contribution of a microdroplet component to the erosion products from vacuum arc cathode spots, when the cathode surface melts to the depth of tens of micrometers during the arc pulse and splashing of the melt due to electro explosive processes in the cathode spots.
{"title":"Erosion of cathode materials with different melting points in a pulsed vacuum arc","authors":"G. Yu Yushkov, V.D. Gridilev, A.G. Nikolaev, E.M. Oks","doi":"10.1016/j.vacuum.2026.115132","DOIUrl":"10.1016/j.vacuum.2026.115132","url":null,"abstract":"<div><div>We present the results of our experiments of specific erosion of 13 different cathode materials in a microsecond pulsed vacuum arc with current 200 A. The specific erosion of materials with relatively high melting points, greater than <em>Т</em><sub>melt</sub> = 650 °C for magnesium, was found to lie within the range from 30 to 100 μg/C, which is typical of erosion in vacuum arc cathode spots. For materials with low melting points, below <em>Т</em><sub>melt</sub> = 328 °C for lead, anomalously high specific erosion in the range from 500 to 1000 μg/C was observed. We find that this high erosion is due to the contribution of a microdroplet component to the erosion products from vacuum arc cathode spots, when the cathode surface melts to the depth of tens of micrometers during the arc pulse and splashing of the melt due to electro explosive processes in the cathode spots.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115132"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-22DOI: 10.1016/j.vacuum.2026.115127
Wei-Chih Chang
Room-temperature exchange bias (EB) in Mn-based noncollinear antiferromagnets has drawn increasing attention for spintronic applications. However, in D019-Mn3Ga/CoFeB system, the EB effect is usually restricted to low temperatures. Here, we demonstrate that introducing a Ru seed layer enables a tunable and anisotropic EB at room temperature. Interfacial strain induced by the Ru layer modulates the lattice symmetry and reconfigures the Dzyaloshinskii-Moriya interaction (DMI). These strain-mediated modifications promote the formation of nanoscale ferromagnetic (FM) clusters driven by the reconfiguration of magnetic octupole symmetry and the displacement of Weyl nodes in momentum space, which act as topological interfacial pinning centers. This selectively enhances the in-plane (IP) EB field to 35.68 Oe while reducing the out-of-plane (OOP) component. The anisotropic EB can be independently controlled by adjusting the Mn3Ga thickness: the IP EB decreases with increasing thickness due to lattice relaxation, whereas the OOP EB increases, revealing distinct interfacial and bulk topological contributions related to the stabilization of the relaxed magnetic octupole state. The observed waist-shaped hysteresis loops indicate an asynchronous reversal mechanism governed by a graded pinning landscape originating from the interplay between lattice-induced DMI and Weyl node dynamics. These results establish that both the Ru seed layer and Mn3Ga thickness are effective tuning parameters for engineering room-temperature anisotropic EB effect, providing a promising route toward noncollinear antiferromagnetic MRAM and orientation-dependent spintronic devices.
{"title":"Engineering anisotropic room-temperature exchange bias in D019-Mn3Ga/CoFeB bilayer grown on Al2O3 substrates via Ru seed layer-induced interface modulation","authors":"Wei-Chih Chang","doi":"10.1016/j.vacuum.2026.115127","DOIUrl":"10.1016/j.vacuum.2026.115127","url":null,"abstract":"<div><div>Room-temperature exchange bias (EB) in Mn-based noncollinear antiferromagnets has drawn increasing attention for spintronic applications. However, in D0<sub>19</sub>-Mn<sub>3</sub>Ga/CoFeB system, the EB effect is usually restricted to low temperatures. Here, we demonstrate that introducing a Ru seed layer enables a tunable and anisotropic EB at room temperature. Interfacial strain induced by the Ru layer modulates the lattice symmetry and reconfigures the Dzyaloshinskii-Moriya interaction (DMI). These strain-mediated modifications promote the formation of nanoscale ferromagnetic (FM) clusters driven by the reconfiguration of magnetic octupole symmetry and the displacement of Weyl nodes in momentum space, which act as topological interfacial pinning centers. This selectively enhances the in-plane (IP) EB field to 35.68 Oe while reducing the out-of-plane (OOP) component. The anisotropic EB can be independently controlled by adjusting the Mn<sub>3</sub>Ga thickness: the IP EB decreases with increasing thickness due to lattice relaxation, whereas the OOP EB increases, revealing distinct interfacial and bulk topological contributions related to the stabilization of the relaxed magnetic octupole state. The observed waist-shaped hysteresis loops indicate an asynchronous reversal mechanism governed by a graded pinning landscape originating from the interplay between lattice-induced DMI and Weyl node dynamics. These results establish that both the Ru seed layer and Mn<sub>3</sub>Ga thickness are effective tuning parameters for engineering room-temperature anisotropic EB effect, providing a promising route toward noncollinear antiferromagnetic MRAM and orientation-dependent spintronic devices.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115127"},"PeriodicalIF":3.9,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-21DOI: 10.1016/j.vacuum.2026.115124
S. Ghalab , Mansour Aouassa , A.K. Aladim , Saud A. Algarni , Majed Alharbi , Mohammed Ibrahim , K.M.A. Saron , Mohammed Bouabdellaoui , Isabelle Berbezier
In this work, we grow and investigate CMOS-compatible Ge quantum dots (Ge QDs) integrated into metal–oxide–semiconductor (MOS) photodetectors, with a focus on their electrical transport and photocurrent response. Crystalline Ge QDs with an average diameter of ≈5.8 nm, hemispherical shape, and a high density (∼5 × 1012 cm−2) are formed by solid-state dewetting of a 1 nm amorphous Ge film grown by molecular beam epitaxy (MBE) on SiO2/Si, subsequently capped with a 45 nm SiO2 layer, and finally converted into MOS Ge-QD photodetectors by depositing transparent AuPd pads. Temperature-dependent current–voltage and capacitance–voltage measurements, complemented by photocurrent analysis, reveal the formation of a Schottky-like MOS photodetector exhibiting a rectification ratio close to 102 and a low dark current. Charge transport is governed by thermionic emission assisted by Fowler–Nordheim tunneling, with the embedded Ge QDs acting as efficient charge-relay centers in the oxide, facilitating carrier injection and reducing the threshold voltage without degrading the capacitive behavior of the structure. Under illumination, the Ge-QD–based MOS photodetectors show a pronounced enhancement of photosensitivity, particularly in the visible spectral range, consistent with strong quantum confinement in the QDs. These results demonstrate that MBE-grown Ge QDs obtained by solid-state dewetting provide a promising platform for the realization of CMOS-compatible, low-power, high-performance optoelectronic devices, especially photodetectors and, more broadly, quantum-dot–engineered solar-cell architectures.
{"title":"CMOS-compatible MBE-grown germanium quantum dots for high-performance photodetectors and solar cells","authors":"S. Ghalab , Mansour Aouassa , A.K. Aladim , Saud A. Algarni , Majed Alharbi , Mohammed Ibrahim , K.M.A. Saron , Mohammed Bouabdellaoui , Isabelle Berbezier","doi":"10.1016/j.vacuum.2026.115124","DOIUrl":"10.1016/j.vacuum.2026.115124","url":null,"abstract":"<div><div>In this work, we grow and investigate CMOS-compatible Ge quantum dots (Ge QDs) integrated into metal–oxide–semiconductor (MOS) photodetectors, with a focus on their electrical transport and photocurrent response. Crystalline Ge QDs with an average diameter of ≈5.8 nm, hemispherical shape, and a high density (∼5 × 10<sup>12</sup> cm<sup>−2</sup>) are formed by solid-state dewetting of a 1 nm amorphous Ge film grown by molecular beam epitaxy (MBE) on SiO<sub>2</sub>/Si, subsequently capped with a 45 nm SiO<sub>2</sub> layer, and finally converted into MOS Ge-QD photodetectors by depositing transparent AuPd pads. Temperature-dependent current–voltage and capacitance–voltage measurements, complemented by photocurrent analysis, reveal the formation of a Schottky-like MOS photodetector exhibiting a rectification ratio close to 10<sup>2</sup> and a low dark current. Charge transport is governed by thermionic emission assisted by Fowler–Nordheim tunneling, with the embedded Ge QDs acting as efficient charge-relay centers in the oxide, facilitating carrier injection and reducing the threshold voltage without degrading the capacitive behavior of the structure. Under illumination, the Ge-QD–based MOS photodetectors show a pronounced enhancement of photosensitivity, particularly in the visible spectral range, consistent with strong quantum confinement in the QDs. These results demonstrate that MBE-grown Ge QDs obtained by solid-state dewetting provide a promising platform for the realization of CMOS-compatible, low-power, high-performance optoelectronic devices, especially photodetectors and, more broadly, quantum-dot–engineered solar-cell architectures.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115124"},"PeriodicalIF":3.9,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-21DOI: 10.1016/j.vacuum.2026.115129
Zhuofu Wei , Xiwen Hu , Shiyu Niu , Yuxin Wang , Zhongliang Liu , Zhenwen Yang , Ying Wang
To obtain the high-strength joint of zirconium alloy and stainless steel for nuclear applications, this study utilized a Ti interlayer for diffusion bonding of Zr-3 alloy and 304L stainless steel. Direct diffusion bonding resulted in the formation of numerous brittle intermetallic compounds, including Zr2(Fe, Ni) and Zr(Fe, Cr)2. The introduction of the Ti interlayer eliminated these phases, and the typical interfacial reaction layer of the joints was Zr-3/(Ti, Zr)/Ti/NiTi/TiFe/TiCr2/(Fe, Cr)/304L. The diffusion layer at the Ti/304L interface was identified as the key factor governing the joint's mechanical properties. Within this layer, TiFe and NiTi phases formed preferentially, followed by TiCr2 and (Fe, Cr) phases. Higher bonding temperatures and longer holding times significantly promoted the interdiffusion of Ti with Fe and Cr from the 304L steel. This enrichment of brittle TiFe and TiCr2 phases at the interface consequently degraded the joint properties. The joint achieved a peak shear strength of 247 MPa under the parameters of 760 °C/60 min/10 MPa, representing a 115 % increase compared to the direct diffusion-bonded joint. The fracture was primarily initiated in the brittle phases, such as TiFe and TiCr2, within the Ti/304L diffusion layer.
{"title":"Enhancement of interfacial structure and mechanical properties of Zr-3 alloy and 304L stainless steel diffusion bonded joint via Ti interlayer introduction","authors":"Zhuofu Wei , Xiwen Hu , Shiyu Niu , Yuxin Wang , Zhongliang Liu , Zhenwen Yang , Ying Wang","doi":"10.1016/j.vacuum.2026.115129","DOIUrl":"10.1016/j.vacuum.2026.115129","url":null,"abstract":"<div><div>To obtain the high-strength joint of zirconium alloy and stainless steel for nuclear applications, this study utilized a Ti interlayer for diffusion bonding of Zr-3 alloy and 304L stainless steel. Direct diffusion bonding resulted in the formation of numerous brittle intermetallic compounds, including Zr<sub>2</sub>(Fe, Ni) and Zr(Fe, Cr)<sub>2</sub>. The introduction of the Ti interlayer eliminated these phases, and the typical interfacial reaction layer of the joints was Zr-3/(Ti, Zr)/Ti/NiTi/TiFe/TiCr<sub>2</sub>/(Fe, Cr)/304L. The diffusion layer at the Ti/304L interface was identified as the key factor governing the joint's mechanical properties. Within this layer, TiFe and NiTi phases formed preferentially, followed by TiCr<sub>2</sub> and (Fe, Cr) phases. Higher bonding temperatures and longer holding times significantly promoted the interdiffusion of Ti with Fe and Cr from the 304L steel. This enrichment of brittle TiFe and TiCr<sub>2</sub> phases at the interface consequently degraded the joint properties. The joint achieved a peak shear strength of 247 MPa under the parameters of 760 °C/60 min/10 MPa, representing a 115 % increase compared to the direct diffusion-bonded joint. The fracture was primarily initiated in the brittle phases, such as TiFe and TiCr<sub>2</sub>, within the Ti/304L diffusion layer.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115129"},"PeriodicalIF":3.9,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.vacuum.2026.115125
Xiao Xi , Xuxu Liu , Wei Jin , Jipeng Zhu , Hai Jin , Xiaoqiu Ye , Changan Chen
In this study, a 13.56 MHz radio frequency power supply was used to generate an external solenoid inductively coupled plasma source. An ion energy mass spectrometer equipped with a Bessel box and quadrupole mass filter was employed to investigate the characteristics of ion in expansion region. The ion species, concentration and their energy distributions with different working gases, including deuterium, nitrogen and their mixtures, have been analyzed by adjusting the gas flow rate or relative concentration over a wide parametric range. The results give the evolution of deuterium series D+/D2+/D3+, nitrogen series N+/N2+/N2D+, and the ammonia series ND+/ND2+/ND3+/ND4+. The ion energy distribution of D3+, N2+ and ND4+ display multi-peak distributions, indicating sheath voltage modulation and frequent collisional production in gas phase. The signal intensities and peak energies of these ions show distinct trends with respect to the gas flow rate. The reaction processes been given to illustrate the transformation path within and between different ion series. The reactions can be divided into three stages: ionization regime, intermediate regime and recombination regime, depending on the overall gas flow rate. And the N2D+ is an effective media during molecular assisted recombination stage. These results benefit plasma processing and chemical synthesis.
{"title":"Distribution of ion energy and concentration in the expansion region of radio-frequency inductive coupled plasmas with deuterium and deuterium-nitrogen mixtures","authors":"Xiao Xi , Xuxu Liu , Wei Jin , Jipeng Zhu , Hai Jin , Xiaoqiu Ye , Changan Chen","doi":"10.1016/j.vacuum.2026.115125","DOIUrl":"10.1016/j.vacuum.2026.115125","url":null,"abstract":"<div><div>In this study, a 13.56 MHz radio frequency power supply was used to generate an external solenoid inductively coupled plasma source. An ion energy mass spectrometer equipped with a Bessel box and quadrupole mass filter was employed to investigate the characteristics of ion in expansion region. The ion species, concentration and their energy distributions with different working gases, including deuterium, nitrogen and their mixtures, have been analyzed by adjusting the gas flow rate or relative concentration over a wide parametric range. The results give the evolution of deuterium series D<sup>+</sup>/D<sub>2</sub><sup>+</sup>/D<sub>3</sub><sup>+</sup>, nitrogen series N<sup>+</sup>/N<sub>2</sub><sup>+</sup>/N<sub>2</sub>D<sup>+</sup>, and the ammonia series ND<sup>+</sup>/ND<sub>2</sub><sup>+</sup>/ND<sub>3</sub><sup>+</sup>/ND<sub>4</sub><sup>+</sup>. The ion energy distribution of D<sub>3</sub><sup>+</sup>, N<sub>2</sub><sup>+</sup> and ND<sub>4</sub><sup>+</sup> display multi-peak distributions, indicating sheath voltage modulation and frequent collisional production in gas phase. The signal intensities and peak energies of these ions show distinct trends with respect to the gas flow rate. The reaction processes been given to illustrate the transformation path within and between different ion series. The reactions can be divided into three stages: ionization regime, intermediate regime and recombination regime, depending on the overall gas flow rate. And the N<sub>2</sub>D<sup>+</sup> is an effective media during molecular assisted recombination stage. These results benefit plasma processing and chemical synthesis.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115125"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.vacuum.2026.115123
Dongdong Chen , Zan Long , Sirong Zhu , Huaxin Liang , Yuan Teng , Cunji Pu , Jikang Yan , Yanqing Lai , Jianhong Yi
The structure of the interfacial layer is important for evaluating the reliability of an electronic package. Herein, we comprehensively investigated the changes in morphology and thickness of intermetallic compounds interlayer during aging, the diffusion of elements during the reflow soldering and isothermal aging, as well as the phase structural and crystallographic relationships among β-Sn, Cu6Sn5, and Cu3Sn phases. After aging, Cu6Sn5/β-Sn interface exhibited special crystallographic relationship, while the angle between and was 174.1°. Cu6Sn5/Cu3Sn interface showed special crystallographic relationship, while the angle between and was 58.7°. The growth patterns of Cu6Sn5 and Cu3Sn phases during isothermal aging were investigated further based on the interface orientation relationship. This study reported the growth of the interface IMCs layer via the interfacial structure of Cu6Sn5/β-Sn, Cu6Sn5/Cu3Sn, and Cu3Sn/Cu, which further improves the orientation relationship of interface phases. Meanwhile, this work provides a valuable basis for improving the reliability of solder service.
{"title":"Research on the phase interface structure and orientation relationship of the intermetallic compounds layer in Sn-3.0Ag-0.5Cu/Cu joints during isothermal aging","authors":"Dongdong Chen , Zan Long , Sirong Zhu , Huaxin Liang , Yuan Teng , Cunji Pu , Jikang Yan , Yanqing Lai , Jianhong Yi","doi":"10.1016/j.vacuum.2026.115123","DOIUrl":"10.1016/j.vacuum.2026.115123","url":null,"abstract":"<div><div>The structure of the interfacial layer is important for evaluating the reliability of an electronic package. Herein, we comprehensively investigated the changes in morphology and thickness of intermetallic compounds interlayer during aging, the diffusion of elements during the reflow soldering and isothermal aging, as well as the phase structural and crystallographic relationships among β-Sn, Cu<sub>6</sub>Sn<sub>5</sub>, and Cu<sub>3</sub>Sn phases. After aging, Cu<sub>6</sub>Sn<sub>5</sub><strong>/</strong>β-Sn interface exhibited special <span><math><mrow><msub><mrow><mo>[</mo><mn>010</mn><mo>]</mo></mrow><mrow><mi>β</mi><mo>−</mo><mi>S</mi><mi>n</mi></mrow></msub><mo>/</mo><mo>/</mo><msub><mrow><mo>[</mo><mn>210</mn><mo>]</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>6</mn></msub><mi>S</mi><msub><mi>n</mi><mn>5</mn></msub></mrow></msub></mrow></math></span> crystallographic relationship, while the angle between <span><math><mrow><msub><mrow><mo>(</mo><mrow><mover><mn>1</mn><mo>‾</mo></mover><mn>01</mn></mrow><mo>)</mo></mrow><mrow><mi>β</mi><mo>−</mo><mi>S</mi><mi>n</mi></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mo>(</mo><mrow><mover><mn>1</mn><mo>‾</mo></mover><mn>21</mn></mrow><mo>)</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>6</mn></msub><mi>S</mi><msub><mi>n</mi><mn>5</mn></msub></mrow></msub></mrow></math></span> was 174.1°. Cu<sub>6</sub>Sn<sub>5</sub><strong>/</strong>Cu<sub>3</sub>Sn interface showed special <span><math><mrow><msub><mrow><mo>[</mo><mn>111</mn><mo>]</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>6</mn></msub><mi>S</mi><mi>n</mi><mn>5</mn></mrow></msub><mo>/</mo><mo>/</mo><msub><mrow><mo>[</mo><mn>001</mn><mo>]</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>3</mn></msub><mi>S</mi><mi>n</mi></mrow></msub></mrow></math></span> crystallographic relationship, while the angle between <span><math><mrow><msub><mrow><mo>(</mo><mrow><mn>3</mn><mover><mn>1</mn><mo>‾</mo></mover><mover><mn>2</mn><mo>‾</mo></mover></mrow><mo>)</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>6</mn></msub><mi>S</mi><msub><mi>n</mi><mn>5</mn></msub></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mo>(</mo><mrow><mn>2</mn><mover><mn>1</mn><mo>‾</mo></mover><mn>0</mn></mrow><mo>)</mo></mrow><mrow><mi>C</mi><msub><mi>u</mi><mn>3</mn></msub><mi>S</mi><mi>n</mi></mrow></msub></mrow></math></span> was 58.7°. The growth patterns of Cu<sub>6</sub>Sn<sub>5</sub> and Cu<sub>3</sub>Sn phases during isothermal aging were investigated further based on the interface orientation relationship. This study reported the growth of the interface IMCs layer via the interfacial structure of Cu<sub>6</sub>Sn<sub>5</sub><strong>/</strong>β-Sn, Cu<sub>6</sub>Sn<sub>5</sub><strong>/</strong>Cu<sub>3</sub>Sn, and Cu<sub>3</sub>Sn/Cu, which further improves the orientation relationship of interface phases. Meanwhile, this work provides a valuable basis for improving the reliability of solder service.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115123"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.vacuum.2026.115102
Guoheng Yu , Detian Li , Huzhong Zhang , Weijun Huang , Changkun Dong , Zhenhua Xi , Gang Li , Zhangyi Zhong , Weidong Kang
Carbon nanotubes (CNTs) are a type of field emission cathode material with broad application potential. Compared with hot filament cathodes, CNTs cathodes possess advantages such as low operating temperature and energy efficiency. In this article, a CNTs electron emitter is integrated into an ionization gauge featuring a straight electron path. A series of tests were performed on the CNTs cathode and the prototype gauge. The optimal operating potential of the prototype gauge was determined through simulations and experiments. The prototype achieved a sensitivity of 0.317 Pa−1 in argon and 0.240 Pa−1 in nitrogen. This prototype gauge exhibits good linearity in the range from 10−6 Pa to 10−3 Pa in argon and nitrogen, while its sensitivity fluctuations are 1.17 % and 3.2 %, and within half an hour, the sensitivity fluctuations in the two gases are 1.6 % and 2.2 % respectively. Under simulated normal operating conditions, the repeatability is less than 3 %. This novel developed ionization gauge has simultaneously achieved high sensitivity and good stability. This study provides insights for the application of CNTs cathodes in the ionization gauges.
碳纳米管是一种具有广泛应用潜力的场发射阴极材料。与热丝阴极相比,CNTs阴极具有工作温度低、能效高等优点。在本文中,将碳纳米管电子发射器集成到具有直电子路径的电离计中。对碳纳米管阴极和原型压力表进行了一系列测试。通过仿真和实验,确定了原型仪表的最佳工作电位。样品在氩气和氮气中的灵敏度分别为0.317 Pa−1和0.240 Pa−1。在10−6 Pa ~ 10−3 Pa的氩气和氮气环境中,样品表具有良好的线性关系,灵敏度波动幅度分别为1.17%和3.2%,半小时内,两种气体的灵敏度波动幅度分别为1.6%和2.2%。在模拟正常工作条件下,重复性小于3%。这种新型电离计具有高灵敏度和良好的稳定性。本研究为碳纳米管阴极在电离计中的应用提供了新的思路。
{"title":"A carbon nanotubes cathode ionization gauge with a straight path of electrons","authors":"Guoheng Yu , Detian Li , Huzhong Zhang , Weijun Huang , Changkun Dong , Zhenhua Xi , Gang Li , Zhangyi Zhong , Weidong Kang","doi":"10.1016/j.vacuum.2026.115102","DOIUrl":"10.1016/j.vacuum.2026.115102","url":null,"abstract":"<div><div>Carbon nanotubes (CNTs) are a type of field emission cathode material with broad application potential. Compared with hot filament cathodes, CNTs cathodes possess advantages such as low operating temperature and energy efficiency. In this article, a CNTs electron emitter is integrated into an ionization gauge featuring a straight electron path. A series of tests were performed on the CNTs cathode and the prototype gauge. The optimal operating potential of the prototype gauge was determined through simulations and experiments. The prototype achieved a sensitivity of 0.317 Pa<sup>−</sup><sup>1</sup> in argon and 0.240 Pa<sup>−</sup><sup>1</sup> in nitrogen. This prototype gauge exhibits good linearity in the range from 10<sup>−6</sup> Pa to 10<sup>−3</sup> Pa in argon and nitrogen, while its sensitivity fluctuations are 1.17 % and 3.2 %, and within half an hour, the sensitivity fluctuations in the two gases are 1.6 % and 2.2 % respectively. Under simulated normal operating conditions, the repeatability is less than 3 %. This novel developed ionization gauge has simultaneously achieved high sensitivity and good stability. This study provides insights for the application of CNTs cathodes in the ionization gauges.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115102"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study introduced the laser powder bed fusion of core-shell AlCrFeCoNi high-entropy alloy (HEA)-reinforced 316L stainless steel matrix composites (MMCs) with enhanced mechanical performance. To prevent diffusion between the HEA and the 316L matrix during the forming process, a core-shell structured HEA-reinforcing phase was prepared by an in-situ hydrolysis reaction of a silicon source salt. The microstructural characteristics and mechanical properties of LPBF-fabricated MMCs containing 20 wt% AlCrFeCoNi were systematically examined. Microstructural analysis revealed that core-shell HEAs with a single BCC phase were homogeneously dispersed within the 316L matrix, effectively transforming the coarse-grained microstructure into a refined one. This grain refinement can be attributed to the heterogeneous nucleation effect induced by the core-shell HEA particles during solidification. The 20 wt% HEA-316L composite exhibited higher strength and fracture toughness, namely a yield strength of 759±2 MPa, ultimate tensile strength of 798±2 MPa, and elongation of 29.6 ± 1.5 %.
{"title":"Fabrication and characterization of core-shell HEA-reinforced 316L composite prepared by LPBF","authors":"Qiqi Chen, Xueli Zhao, Shaoning Niu, Xini Xiong, Yongjuan Dai, Shaofeng Yang","doi":"10.1016/j.vacuum.2026.115122","DOIUrl":"10.1016/j.vacuum.2026.115122","url":null,"abstract":"<div><div>This study introduced the laser powder bed fusion of core-shell AlCrFeCoNi high-entropy alloy (HEA)-reinforced 316L stainless steel matrix composites (MMCs) with enhanced mechanical performance. To prevent diffusion between the HEA and the 316L matrix during the forming process, a core-shell structured HEA-reinforcing phase was prepared by an in-situ hydrolysis reaction of a silicon source salt. The microstructural characteristics and mechanical properties of LPBF-fabricated MMCs containing 20 wt% AlCrFeCoNi were systematically examined. Microstructural analysis revealed that core-shell HEAs with a single BCC phase were homogeneously dispersed within the 316L matrix, effectively transforming the coarse-grained microstructure into a refined one. This grain refinement can be attributed to the heterogeneous nucleation effect induced by the core-shell HEA particles during solidification. The 20 wt% HEA-316L composite exhibited higher strength and fracture toughness, namely a yield strength of 759±2 MPa, ultimate tensile strength of 798±2 MPa, and elongation of 29.6 ± 1.5 %.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"247 ","pages":"Article 115122"},"PeriodicalIF":3.9,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}