Meeting minutes

Present: Raymond and myself; Sergey and Khalid (partly) Location: Nano Building Time: 2 PM Objective: Meeting called to ask questions about the results from the SEM study of ink coating. Agenda:

• He will give me 3 cantilevers for SEM inspection. (bare, dipped into acetonitrile-thiol solution, and rinsed with ethanol). A SEM session reserved on Monday, October 25.
• The SEM study results will be presented during the DPN subgroup meeting next Tuesday on October 26.
• I will bring an FPN chip for him to test on his AFM.
• Ink well will be used to coat cantilevers with thiol molecules and they will be inspected under SEM. I need to make an appointment with Raymond to use the ink well system.
• Suggestion from Khalid. Three different coating methods with two different types of molecule can be combined for the SEM study. The 3 methods include dipping, sublimation, and ink well. MHA and ODT can be used as molecules. DNA can be tried, but the sublimation method cannot be used because it will decompose the DNA. In addition, if possible, wettability of tips can be modified by chemical coating on tips before putting molecules on them. In that way, the effect of the pre-coating on molecular coating can be inspected through SEM.
• Literature search: Lee, Mirkin, JACS 2003 - indirect patterning of proteins because it is hard to coat protein over AFM tips. Sheehan, Adv. Mater. 2004 - He used SiCl3 group attached to the end of thiol molecules for patterning. Mirkin group claimed that it was not possible previously. P. Collier, JACS 2004 - DNP on Si.
• The default contact force they are using in the CP AFM is 2.5 nN.