2]] monolayer derivatization and found that DDPA was connected to Al mainly by bidentate P-O-Al bonds.
The treated Al surfaces were used immediately to DDPA derivatization to avoid contamination which will weaken or even block the interaction between the DDPA headgroups and the Al surfaces.
Crystalline DDPA powder (from Alfa Aesar, 93% purity, Ward Hill, MA) was heated to 100[degrees]C to eliminate moisture prior to use.
Scanning electron microscopy (SEM) and AFM were conducted to characterize the morphology of Al, SU-8, and DDPA surfaces, respectively.
Since the thicknesses of Al and DDPA layers were relatively small, coating of Al and DDPA layers did not change the morphology of SU-8 surfaces.
Since the thickness of DDPA monolayer is about 2 nm, the morphology of DDPA/Al surface could be described as multilayer and island structures, which were further demonstrated by XPS measurements.
Kim's impact as the head of DDPA is immeasurable," said Scott Jones, chairman of DDPA's Board of Directors.
I will always treasure my time at DDPA, and I am proud of what we've been able to accomplish over the years," Volk said.