Liyan LAI

Mrs. Liyan LAI


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 July 2023 in Micromachines
Verified
Journal Article
Open access
PDF file
LLLiyan LAI
Liyan LAI
BNBing Niu
Bing Niu
YBYuxiao Bi
Yuxiao Bi
YLYigui Li
Yigui Li
Zhuoqing YangZhuoqing Yang
Zhuoqing Yang
With the advancement of semiconductor technology, chip cooling has become a major obstacle to enhancing the capabilities of power electronic systems. Traditional electronic packaging materials are no longer able to meet the heat dissipation requirements of high-performance chips. High thermal conductivity (TC), low coefficient of thermal expansion (CTE), good mechanical properties, and a rich foundation in microfabrication techniques are the fundamental requirements for the next generation of electronic packaging materials. Currently, metal matrix composites (MMCs) composed of high TC matrix metals and reinforcing phase materials have become the mainstream direction for the development and application of high-performance packaging materials. Silicon carbide (SiC) is the optimal choice for the reinforcing phase due to its high TC, low CTE, and high hardness. This paper reviews the research status of SiC-reinforced aluminum (Al) and copper (Cu) electronic packaging materials, along with the factors influencing their thermo-mechanical properties and improvement measures. Finally, the current research status and limitations of conventional manufacturing methods for SiC-reinforced MMCs are summarized, and an outlook on the future development trends of electronic packaging materials is provided.

1 January 2024 in REVIEWS ON ADVANCED MATERIALS SCIENCE
Verified
Journal Article
Open access
PDF file
LLLiyan LAI
Liyan LAI
YBYuxiao Bi
Yuxiao Bi
BNBing Niu
Bing Niu
GYGuanliang Yu
Guanliang Yu
YLYigui Li
Yigui Li
QXQiu Xu
Qiu Xu
In recent decades, with the advancement of micro-electro-mechanical systems technology, traditional materials have become insufficient to meet the demands of cutting-edge technology for various material properties. Composites have attracted widespread attention as an effective and viable solution. Silicon carbide whiskers (SiCw) have emerged as excellent reinforcements due to their high thermal conductivity, low thermal expansion coefficient, high melting point, superior mechanical properties, and high chemical stability. This article provides a comprehensive review of the reinforcement mechanisms and current research state of SiCw-reinforced composites. The reinforcement mechanisms include mainly grain refinement, load transfer, and crack bridging. The composites are categorized based on the type of the matrix: ceramic-based, metal-based, and polymer-based composites. The influence and parameter performance of the reinforcement mechanism on SiCw-reinforced composite materials with different matrices vary. However, the key to improving SiCw-reinforced composites lies in understanding the interplay of properties between the matrix and the reinforcement, as well as the ordered and regular distribution and binding at the interface. Finally, the current state and limitations of SiCw-reinforced composites are summarized, and future development trends are discussed. This article represents a great contribution to the future applications of SiCw-reinforced composite materials.

14 September 2023 in Micromachines
Verified
Journal Article
Open access
PDF file
LLLiyan LAI
Liyan LAI
GYGuanliang Yu
Guanliang Yu
WGWang Guilian
Wang Guilian
YLYigui Li
Yigui Li
Guifu DingGuifu Ding
Guifu Ding
Zhuoqing YangZhuoqing Yang
Zhuoqing Yang
The microspring is a typical type of device in MEMS devices, with a wide range of application scenarios and demands, among which a popular one is the microelectroformed nickel-based planar microspring prepared by the UV-LIGA technology based on the SU-8 adhesive. It is worth noting that the yield strength of the electrodeposited nickel microstructure is low, and the toughness of the structure is not high, which is unbeneficial for the enduring and stable operation of the spring. The paper mainly presents the methods of preparing high-aspect-ratio Ni/SiCw microstructures for MEMS devices based on UV-LIGA technology, developing Ni/SiCw-based microspring samples with a thickness of 300 μm, and applying a DMA tensile tester for mechanical property tests and characterization. In addition, the paper explores the influence of heat treatment at 300 °C and 600 °C on the tensile properties and microstructure of composite coatings. The results show that the W-form microspring prepared from Ni/SiCw composites not only has a wider linear range (about 1.2 times wider) than that of pure nickel material but also has a stronger resistance capacity to plastic deformation, which is competent for MEMS device applications in environments below 300 °C. The research provides a frame of reference and guidance for improving the stable cyclic operating life of such flat springs.

18 June 2024 in Nanomaterials
Verified
Journal Article
Open access
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BNBing Niu
Bing Niu
DXDongdong Xie
Dongdong Xie
ZZZhang Zhang
Zhang Zhang
YBYuxiao Bi
Yuxiao Bi
YLYigui Li
Yigui Li
LLLiyan LAI
Liyan LAI
With the rapid development of electronic technology and large-scale integrated circuit devices, it is very important to develop thermal management materials with high thermal conductivity. Silicon carbide whisker-reinforced copper matrix (Cu/SiCw) composites are considered to be one of the best candidates for future electronic device radiators. However, at present, most of these materials are produced by high-temperature and high-pressure processes, which are expensive and prone to interfacial reactions. To explore the plating solution system suitable for SiCw and Cu composite electroplating, we tried two different Cu-based plating solutions, namely a Systek UVF 100 plating solution of the copper sulfate (CuSO4) system and a Through Silicon Via (TSV) plating solution of the copper methanesulfonate (Cu(CH3SO3)2) system. In this paper, Cu/SiCw composites were prepared by composite electrodeposition. The morphology of the coating under two different plating liquid systems was compared, and the mechanism of formation of the different morphologies was analyzed. The results show that when the concentration of SiCw in the bath is 1.2 g/L, the surface of the Cu/SiCw composite coating prepared by the CuSO4 bath has more whiskers with irregular distribution and the coating is very smooth, but there are pores at the junction of the whiskers and Cu. There are a large number of irregularly distributed whiskers on the surface of the Cu/SiCw composite coating prepared with the copper methanesulfonate (Cu(CH3SO3)2) system. The surface of the composite is flat, and Cu grows along the whisker structure. The whisker and Cu form a good combination, and there is no pore in the cross-section of the coating. The observation at the cross-section also reveals some characteristics of the toughening mechanism of SiCw, including crack deflection, bridging and whisker pull-out. The existence of these mechanisms indicates that SiCw plays a toughening role in the composites. A suitable plating solution system was selected for the preparation of high-performance Cu/SiCw thermal management materials with the composite electrodeposition process.

9 May 2025 in Nanomaterials
Verified
Journal Article
Open access
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ZZZhang Zhang
Zhang Zhang
LLLiyan LAI
Liyan LAI
YLYan Luo
Yan Luo
Zhuoqing YangZhuoqing Yang
Zhuoqing Yang
Guifu DingGuifu Ding
Guifu Ding
In this study, high-performance SiC whisker (SiCw)-reinforced Cu matrix functionally graded materials (FGMs) were achieved through the synergy of numerical simulation and co-electrodeposition and then successfully applied as the interface of Cu and Si. A comprehensive numerical simulation framework was developed to investigate the influence of gradient transition modes and the maximum volume fraction of SiCw on the thermal–mechanical properties in the different gradient structures. The optimized FGMs via numerical simulation were fabricated using a co-electrodeposition technique, producing a 100 μm thick coating with a SiCw volume fraction gradient ranging from 0% to 40%. The interface of Cu and SiC was void free in the FGMs and the SiCw was coated by nano-scale Cu grains during the electroplating process. The coefficient of thermal expansion in FGMs was higher than 9.78 × 10−6 K−1, which was the coefficient of thermal expansion in the Cu-40% vol. SiCw, and lower than 16.4 × 10−6 K−1, which was the coefficient of thermal expansion in pure Cu. Notably, the bonding interface area between the Cu/Si joint with the gradient-structured FGMs was more than twice that of non-graded materials. The enhanced thermal–mechanical performance was attributed to the synergistic effects of the nano-scale grain-reinforced SiCw-Cu interface and an optimized stress distribution achieved by the gradient structure.

20 February 2026 in Microsystem Technologies
Verified
Journal Article
Closed access
PDF file
LLLiyan LAI
Liyan LAI
YBYuxiao Bi
Yuxiao Bi
FQFeng Qian
Feng Qian
WGWang Guilian
Wang Guilian
YLYigui Li
Yigui Li
Guifu DingGuifu Ding
Guifu Ding