1. Technologies for Realizing Carbon Nanotube Vias XU Hua 20171013 26 Nov 2014

2. Content Introduction of CNT technology Types of via fabrication process –Top-down fabrication process –Bottom-up fabrication process Problems to solve 2

3. Introduction of CNT technology Trends of applying CNT technology Benefits: –CNT is very good heat conductor to allow faster processing thermal conductivity: 3500 W·m −1 ·K −1 Defects: –The resistance of CNT is not low enough Uncertainty: –Toxicity of CNT and its catalyst 3

4. Top-down fabrication process Synthesizing: Carbon nanotube (CNT) are grown from catalyst: Co, Fe, Ni Gas source: CH4, C2H2 etc; H2 & N2 as etching gas equipment for catalyst deposition schematic of top-down process 4

5. Top-down fabrication process Examples of top-down process 5

6. Top-down fabrication process Result of top-down process----large variation 6

7. Bottom-up fabrication process Schematic of bottom-up process Advantages: More stable structure; Chemical mechanical polishing result in smooth surface; The CNT have the same height. Disadvantages: Tetraethylorthosilicate CVD form voids inside; CNT are not perfectly aligned. 7

8. Bottom-up fabrication process Defect in bottom-up process 8

9. Problems to solve Resistance not low enough –0.59 Ω for 2-μm CNT via in top-down process –300 kΩ for 2-μm CNT via in bottom-up process –Higher CNT density will decrease the resistance The structure synthesized varies a lot –The two technologies can be combined to have better CNT structure References: [1] Shintaro Sato, Mizuhisa Nihei, Atsushi Mimura, Novel approach to fabricating carbon nanotube via interconnects usingsize-controlled catalyst nanoparticles, 2006 IEEE [2] Makoto Suzuki,Yusuke Ominami, Takashi Sekiguchi, and Cary Y. Yang, Secondary electron imaging of embedded defects in carbon nanofiber via interconnects, 2008 American Institute of Physics [3] Jun Li, Qi Ye, Alan Cassell, Hou Tee Ng, Bottom-up approach for carbon nanotube interconnects, January 2003, Applied Physics Letters 9

10. Thank you! 10