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The development of novel doping strategies compatible with high‐resolution patterning and low cost, large‐scale manufacturing is critical to the future development of electronic devices. Here, an approach to achieve nanoscale site‐specific doping of Si wafer using DNA as both the template and the dopant carrier is reported. Upon thermal treatment, the phosphorous atoms in the DNA diffuse into Si wafer, resulting in doping within the region right around the DNA template. A doping length of 30 nm is achieved for 10 s of thermal treatment at 1000 °C. Prototype field effect transistors are fabricated using the DNA‐doped Si substrate; the device characteristics confirmed that the Si is n‐doped. It is also shown that this approach can be extended to achieve both n‐type and p‐type site‐specific doping of Si by using DNA nanostructures to pattern self‐assembled monolayers. This work shows that the DNA template is a dual‐use template that can both pattern Si and deliver dopants.

 

To identify superior thermal contacts to graphene we implement a high throughput methodology that systematically explores the Ni-Pd alloy composition spectrum and the effect of Cr adhesion layer thickness on the thermal interface conductance with monolayer CVD graphene. Frequency domain thermoreflectance measurements of two independently prepared Ni- Pd/Cr/graphene/SiO2 samples both identify a maximum in the metal/graphene/SiO2 junction thermal interface conductance of 114± (39, 25) MW/m2K and 113± (33, 22) MW/m2K at ~10 atomic percent Pd in Ni—nearly double the highest reported value for pure metals and three times that of pure Ni or Pd. The presence of Cr, at any thickness, suppresses this maximum. Although the origin of the peak is unresolved, we find that it correlates to a region of the Ni-Pd phase diagram that exhibits a miscibility gap. Cross sectional imaging by high resolution transmission electron microscopy identifies striations in the alloy at this particular composition, consistent with separation into multiple phases. Through this work, we draw attention to alloys in the search for better contacts to 2D materials for next generation devices.