SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Fu Yifeng 1984) "

Sökning: WFRF:(Fu Yifeng 1984)

Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
21.
  • Fu, Yifeng, 1984, et al. (författare)
  • A complete carbon-nanotube-based on-chip cooling solution with very high heat dissipation capacity
  • 2012
  • Ingår i: Nanotechnology. - 1361-6528 .- 0957-4484. ; 23:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Heat dissipation is one of the factors limiting the continuous miniaturization of electronics. In the study presented in this paper, we designed an ultra-thin heat sink using carbon nanotubes (CNTs) as micro cooling fins attached directly onto a chip. A metal-enhanced CNT transfer technique was utilized to improve the interface between the CNTs and the chip surface by minimizing the thermal contact resistance and promoting the mechanical strength of the microfins. In order to optimize the geometrical design of the CNT microfin structure, multi-scale modeling was performed. A molecular dynamics simulation (MDS) was carried out to investigate the interaction between water and CNTs at the nanoscale and a finite element method (FEM) modeling was executed to analyze the fluid field and temperature distribution at the macroscale. Experimental results show that water is much more efficient than air as a cooling medium due to its three orders-of-magnitude higher heat capacity. For a hotspot with a high power density of 5000 W cm(-2), the CNT microfins can cool down its temperature by more than 40 degrees C. The large heat dissipation capacity could make this cooling solution meet the thermal management requirement of the hottest electronic systems up to date.
  •  
22.
  • Fu, Yifeng, 1984, et al. (författare)
  • Application of through silicon via technology for in situ temperature monitoring on thermal interfaces
  • 2010
  • Ingår i: Journal of Micromechanics and Microengineering. - 0960-1317. ; 20:2, s. id 025027 (5 pp)-
  • Tidskriftsartikel (refereegranskat)abstract
    • In this paper, a series of micro-machining processes have been developed to fabricate a test platform with the ability of in situ temperature monitoring on thermal interface behaviour. Through silicon vias (TSVs) with an aspect ratio up to 13 using Cu as a conductor have been applied to connect an array of platinum-based temperature sensors directly deposited on the thermal interfaces to be measured. The sensors are subsequently calibrated by an industry standard resistance temperature detector. Results show that the temperature sensors function normally in a temperature range up to 250 degrees C. This demonstrates the successful deposition of temperature-sensing materials and their good connection to the TSVs. The realization of direct precise temperature measurement on the thermal interface of this test platform enables thermal characterization with a high accuracy.
  •  
23.
  • Fu, Yifeng, 1984, et al. (författare)
  • Carbon nanotube growth on different underlayers for thermal interface material application
  • 2016
  • Ingår i: IMAPS Nordic Annual Conference 2016 Proceedings.
  • Konferensbidrag (refereegranskat)abstract
    • Thermal interface material (TIM) is a critical component in thermal management of high density packaging systems since both the reliability and lifetime of microsystems are dependent on how the heat is dissipated. Carbon nanotubes (CNTs) are promising candidate for development of TIMs due to their excellent thermal and mechanical properties. The thermal conductivity of CNTs can be up to 3000 W/mK in the longitudinal direction which acts as ideal heat transfer path. However, the huge interfacial thermal resistance between CNTs and contact surface hinders the exploitation of CNTs as TIMs. In this paper, we will focus on the growth of CNTs on various substrates and underlayers and analyze the interaction between catalyst and underlayer materials. Microscopic analysis is performed to characterize the quality of the CNT materials and monitor the diffusion of Fe particles into different barrier layers. Thermal conductivity of the CNT TIMs will be measured to examine the performance of the materials.
  •  
24.
  •  
25.
  • Fu, Yifeng, 1984 (författare)
  • Carbon Nanotubes for Electronic Packaging: Growth, Novel Devices and 3D Networks
  • 2012
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • Carbon nanotubes (CNTs) have shown great potential of application in electronics because of their attractive physical properties, such as high surface-to-volume ratio, high electron mobility, high Young’s modulus, high thermal conductivity, low thermal expansion coefficient, etc. However, many obstacles are yet to be removed to use CNTs as building blocks in electronic systems. This thesis is attempting to overcome some of the challenges that hinder the implementation of CNTs in electronic packaging.The first section concerns about the most essential issue in CNT application, the growth of CNTs. A new method is presented and it is capable of highly selective growth of CNTs, which is one of the main challenges in the CNT technology field. By growing CNTs on gold films using thermal chemical vapor deposition (TCVD) method, the number of CNT walls can be well controlled and statistical study shows that a selectivity of 79.4% can be achieved for double-walled CNTs.The second section presents the design and fabrication of a CNT based on-chip cooler, attempting to utilize CNTs for heat dissipation from electronic systems. A test platform with integrated heating elements and temperature sensors is designed and fabricated for this purpose. A new CNT transfer technology is developed to transplant the CNT microfins with pre-defined structures to desired positions on the test platform. Electrical and mechanical characterizations demonstrate that the CNT-substrate interface has been dramatically improved after the transfer process therefore addressed two of the most challenging tasks on integrating CNTs into electronics, i.e. decreasing the huge interfacical contact resistance and improving the weak adhesion between CNTs and substrates. A double-coated single photoresist structure for thick materials deposition is also developed to facilitate and simplify the CNT transfer process. Multi-scale modeling is performed to help design the CNT microfin structure. A molecular dynamics simulation (MDS) is carred out to investigate the interaction between water and CNTs at the nanoscale and a finite element method (FEM) modeling is executed to analyze the fluid field and temperature distribution at the macroscale. A novel packaging process using polydimethylsiloxane (PDMS) is also developed to assemble the CNT microfins, the test platform, the fluid channel and the supporting substrate into an integrated system. Cooling experiments have demonstrated the high efficiency of the CNT-based on-chip cooler.The third section describes a novel concept to grow covalently bonded three dimensional CNT networks, which is potentially applicable to facilitate thermal transportation in micro systems. A nickel nitrate dissolved polymer is electrospun into inter-connected porous nano fiber networks acting as precursor. The polymer fibers are then burned out and nickel nitrate is decomposed at high temperature into nickel oxide fibers. These fibers are subsequently reduced into pure nickel in hydrogen environment. The as-reduced nickel nano fiber network serves as catalyst to grow graphite layers on their surfaces. Ultimately, the nickel core is etched by iron chloride so that graphite tubes, i.e. CNT structures are left. Since the nickel fibers are inter-connected with each other and graphite layers can only grow on the surface, the as-grown CNT network is covalently bonded. Atomic force microscopy (AFM) based bending tests show that the Young’s modulus of the as-grown CNTs is about 〖391〗_(-172)^(+270) GPa, and the covalently bonded CNT structure can effectively distribute external loading throughout the network to improve the mechanical strength of the material.
  •  
26.
  •  
27.
  • Fu, Yifeng, 1984, et al. (författare)
  • Development of a test platform for thermal characterization using through-silicon-via technology
  • 2009
  • Ingår i: IMAPS Nordic Annual Conference 2009; Tonsberg; Norway; 13 September 2009 through 15 September 2009. ; , s. 35-38
  • Konferensbidrag (refereegranskat)abstract
    • In order to look into the heat transfer mechanism and improve the thermal performance of an electronic component, a thermal test platform has been designed and fabricated. A series of micro-machining processes have been developed to make the test platform. The Through-Silicon-Via technique using Cu as a conductor has been used to fabricate the temperature sensors in order to realize an in-situ temperature monitoring on a thermal interface. Pt-based temperature sensor array has been deposited on the chip and calibrated by an industry standard RTD. Results show that the Pt sensors work well which demonstrates the successful deposition of temperature sensing materials and good interconnection between through-hole vias and IC components. This indicates that the test platform can be used for thermal interface material characterization as well as 3D electronics reliability studies.
  •  
28.
  • Fu, Yifeng, 1984, et al. (författare)
  • Graphene related materials for thermal management
  • 2020
  • Ingår i: 2D Materials. - : IOP PUBLISHING LTD. - 2053-1583. ; 7:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Almost 15 years have gone ever since the discovery of graphene as a single atom layer. Numerous papers have been published to demonstrate its high electron mobility, excellent thermal and mechanical as well as optical properties. We have recently seen more and more applications towards using graphene in commercial products. This paper is an attempt to review and summarize the current status of the research of the thermal properties of graphene and other 2D based materials including the manufacturing and characterization techniques and their applications, especially in electronics and power modules. It is obvious from the review that graphene has penetrated the market and gets more and more applications in commercial electronics thermal management context. In the paper, we also made a critical analysis of how mature the manufacturing processes are; what are the accuracies and challenges with the various characterization techniques and what are the remaining questions and issues left before we see further more applications in this exciting and fascinating field.
  •  
29.
  • Fu, Yifeng, 1984, et al. (författare)
  • Post-Growth Processing of Carbon Nanotubes for Interconnect Applications - A Review
  • 2016
  • Ingår i: 2016 6th Electronic System-Integration Technology Conference (Estc). ; , s. Article no 7764713-
  • Konferensbidrag (refereegranskat)abstract
    • Interconnect is one of the most important functions of packaging technology. It delivers power and signals into and out of electronic systems. The performance and reliability of microsystems are dependent on the interconnect quality. This paper reviews the chip-level interconnects based on carbon nanotubes (CNTs), this includes their applications for both on-chip and off-chip interconnects. Various post-growth processing of CNTs, such as doping, densification, transfer, metallization, etc., for the improvement of their performance will be reviewed.
  •  
30.
  • Fu, Yifeng, 1984, et al. (författare)
  • Selective growth of double-walled carbon nanotubes on gold films
  • 2012
  • Ingår i: Materials Letters. - 0167-577X. ; 72, s. 78-80
  • Tidskriftsartikel (refereegranskat)abstract
    • Growth of high-quality vertical aligned carbon nanotube (CNT) structures on silicon supported gold (Au) films by thermal chemical vapor deposition (TCVD) is presented. Transmission electron microscopy (TEM) images show that the growth is highly selective. Statistical study reveals that 79.4% of the as-grown CNTs are double-walled. The CNTs synthesized on Au films are more porous than that synthesized on silicon substrates under the same conditions. Raman spectroscopy and electrical characterization performed on the as-grown double-walled CNTs (DWNTs) indicate that they are competitive with those CNTs grown on silicon substrates. Field emission tests show that closed-ended DWNTs have lower threshold field than those open-ended.
  •  
Skapa referenser, mejla, bekava och länka
 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy