Abstract High thermal conductivity electronic materials are critical components for high-performance electronic and photonic devices as both active functional materials and thermal management materials. We report an isotropic high thermal conductivity exceeding 500 W m −1 K −1 at room temperature in high-quality wafer-scale cubic silicon carbide (3C-SiC) crystals, which is the second highest among large crystals (only surpassed by diamond). Furthermore, the corresponding 3C-SiC thin films are found to have record-high in-plane and cross-plane thermal conductivity, even higher than diamond thin films with equivalent thicknesses. Our results resolve a long-standing puzzle that the literature values of thermal conductivity for 3C-SiC are lower than the structurally more complex 6H-SiC. We show that the observed high thermal conductivity in this work arises from the high purity and high crystal quality of 3C-SiC crystals which avoids the exceptionally strong defect-phonon scatterings. Moreover, 3C-SiC is a SiC polytype which can be epitaxially grown on Si. We show that the measured 3C-SiC-Si thermal boundary conductance is among the highest for semiconductor interfaces. These findings provide insights for fundamental phonon transport mechanisms, and suggest that 3C-SiC is an excellent wide-bandgap semiconductor for applications of next-generation power electronics as both active components and substrates. 
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                            Influence of processing conditions on the titanium–aluminum contact metallization on a silicon wafer for thermal management
                        
                    
    
            There is a growing need for digital and power electronics to deliver higher power for applications in batteries for electric vehicles, energy sources from wind and solar, data centers, and microwave devices. The higher power also generates more heat, which requires better thermal management. Diamond thin films and substrates are attractive for thermal management applications in power electronics because of their high thermal conductivity. However, deposition of diamond by microwave plasma enhanced chemical vapor deposition (MPECVD) requires high temperatures, which can degrade metallization used in power electronic devices. In this research, titanium (Ti)–aluminum (Al) thin films were deposited by DC magnetron sputtering on p-type Si (100) substrates using a physical mask for creating dot patterns for measuring the properties of the contact metallization. The influence of processing conditions and postdeposition annealing in argon (Ar) and hydrogen (H2) at 380 °C for 1 h on the properties of the contact metallization is studied by measuring the I-V characteristics and Hall effect. The results indicated a nonlinear response for the as-deposited films and linear ohmic contact resistance after postannealing treatments. In addition, the results on contact resistance, resistivity, carrier concentration, and Hall mobility of wafers extracted from Ti–Al metal contact to Si (100) are presented and discussed. 
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                            - Award ID(s):
- 2122495
- PAR ID:
- 10429795
- Publisher / Repository:
- Journal of Vacuum Science and Technology
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology B
- Volume:
- 41
- Issue:
- 4
- ISSN:
- 2166-2746
- Page Range / eLocation ID:
- 042208
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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