Transfer printing of patterned metal films using parylene C coated surfaces
Successful transfer printing of aluminum (Al), copper (Cu), silver (Ag), nickel (Ni) and gold (Au) films is demonstrated. Previously, Al, Cu, Ag, and Ni films have exhibited relatively strong adhesion to silicon (Si) substrates resulting in poor transfer printing results. To overcome this limitation, Si wafers were coated with parylene C before metals deposition. Surface energy calculations determined from contact angle measurements confirm parylenes suitability for the transfer printing process. Metal films were photolithographically patterned onto parylene C coated Si wafers and then transfer printed onto either polyethylene naphthalene (PEN), polycarbonate (PC) or Kapton substrates. Resistance measurements were taken both before and after printing. Calculated resistivity values were close to bulk materials and no significant drop in resistivity was observed after printing, indicating that the printed metal films are of high quality.
transfer printing flexible electronics surface treatments