Qiran Xiao

Research Interests

I studied subjects ranging from interface reliability to self-assembled novel structures. A broad range of materials characterization techniques has been learned and successfully applied, including the most sophisticated and state-of-the-art Transmission Electron Microscopy (TEM).

Specifically, my time has been devoted to

1. structural and chemical characterization of self-assembled molecular layers
2. surface functionalization of metals and semiconductor materials
3. reliability/mechanical stability characterizations of thin-film structures

Metal Adhesion

Simultaneous Cu-oxide Reduction and Hybrid-layer Formation

The presence of weak Cu-oxide has detrimental implications for the adhesion, moisture sensitivity, stress- and electro-migration of Cu bondlines in advanced packaging, often leading to premature device failure. We developed a novel, low-cost, single-step sol-gel synthetic route capable of reducing the weak Cu-oxide while simultaneously depositing a high-performance hybrid layer (HL). The HL acts both as an adhesion layer at the Cu/epoxy interface, as well as a barrier film that prevents moisture degradation and Cu stress- and electro-migration. 

My work showing the grain structure of the Cu film supported on the Si substrate. Image was taken using the sperical-aberration corrected (environmental) Transmission Electron Microscope (TEM) at 300 kV at the Stanford Nano Shared Facility (SNSF).

Semiconductor Adhesion

Exploring the Kinetics of Hybrid-layer Formation

The strength of bonding at epoxy/SiO₂ interface and its susceptibility to environmental degradation have a profound impact on the lifetime and reliability of microelectronic devices. We examined the interface’s adhesion improvement as a result of hybrid-layer incorporation and the kinetics of hydrolysis and polycondensation of the molecular precursors.

Publications

• Q. R. Xiao, B. Watson, R. H. Dauskardt, “Organothiol-Based Hybrid-Layer Strategy for High-Performance Copper Adhesion and Stress-Migration via Simultaneous Oxide Reduction”, Adv. Mater. Interfaces., 2016, 3, 1600118.
• Q. R. Xiao, M. Giachino, R. H. Dauskardt, “Controlling Kinetics of Heterogeneous Sol–Gel Solution for High-Performance Adhesive Hybrid Films”, J. of Sol-Gel Sci and Tech, 2016, 77, 620-626.
• Q. R. Xiao, Y. P. Chen, T. Bereau, Y. F. Shi, “An in-silico walker”, Chemical Physics Letters, 2016, 659, 6-9.
• Q. R. Xiao, L. P. Huang, Y. F. Shi, “Suppression of Shear Banding in Amorphous ZrCuAl Nanopillars by Irradiation”, J. Appl. Phys., 2013, 113.
• P.J. Lezzi, Q.R. Xiao, M. Tomozawa, T. A. Blanchet, C.R. Kurkjian, “Strength Increase of Silica Glass Fibers by Surface Stress Relaxation: A New Mechanical Strengthening Method”, J. of Non-Crystalline Solids, 2013, 379, 95-106.
• Q. R. Xiao, H. W. Sheng, Y. F. Shi, “Dominant Shear Band Observed in Amorphous ZrCuAl Nanowires under Simulated Compression”, MRS Communications, 2012, 2, 13-16.

Conference Proceedings and Presentations

• Q. R. Xiao, B. Watson, R. H. Dauskardt, “Organothiol-Based Hybrid-Layer Strategy for High-Performance Copper Adhesion and Stress-Migration via Simultaneous Oxide Reduction”, Materials Research Society Spring Meeting, Phoenix, Arizona, March, 2016.
• Q. R. Xiao, B. Watson, R. H. Dauskardt, “Low-Cost, Single-Step Hybrid Bond/Barrier Films for Cu Bondlines in Advanced Packaging”, Materials Research Society (MRS) Spring Meeting, San Francisco, CA, April, 2015.
• Q. R. Xiao, B. Watson, R. H. Dauskardt, “Low-Cost, Single-Step Hybrid Bond/Barrier Films for Cu Bondlines in Advanced Packaging”, SystemX Conference, Stanford University, November, 2014.
• Q. R. Xiao, L. P. Huang, Y. F. Shi, “Irradiation suppresses shear banding in Zr-based MG system”, American Physical Society March Meeting, Boston, March, 2012.
• Q. R. Xiao, H. W. Sheng, Y. F. Shi, “Shear band formation in Zr-based MG system”, University Conference on Glass Science, Rensselaer Polytechnic Institute, August, 2011.

Awards

• Enlight Foundation Graduate Fellowship (2013) 
• Matthew Albert Hunter Prize in Metallurgical Engineering (2013)
• Summa Cum Laude (2013)
• Founders Award of Excellence (2012)