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Effects of wet chemical treatment and thermal cycle conditions on the quantitative interfacial adhesion energy of Cu/SiNx thin film interfaces were evaluated by 4-point bending test method. The test samples were cleaned by chemical treatment after Cu chemical-mechanical polishing (CMP). The thermal cycle test between Cu and SiNx capping layer was experimented at the temperature, -45 to 175 o C for 250 cycles. The measured interfacial adhesion energy increased from 10.57 to 14.87 J/m 2 after surface chemical treatment. After 250 thermal cycles, the interfacial adhesion energy decreased to 5.64 J/m 2 and 7.34 J/m 2 for without chemical treatment and with chemical treatment, respectively. The delaminated interfaces were confirmed as Cu/SiNx interface by using the scanning electron microscope and energy dispersive spectroscopy. From X-ray photoelectron spectroscopy analysis results, the relative Cu oxide amounts between SiNx and Cu decreased by chemical treatment and increased after thermal cycle. The thermal stress due to the mismatch of thermal expansion coefficient during thermal cycle seemed to weaken the Cu/SiNx interface adhesion, which led to increased CuO amounts at Cu film surface.

Effects of annealing on the properties of P- and B-implanted Si for interdigitated back contact (IBC) solar cells were investigated with annealing temperature of from 950 to 1050 °C. P-implanted samples annealed at 950 °C were enough to activate dopants and recover the damage by implantation. As the annealing temperature was increased, the diode properties of P-implanted samples were degraded, while that of B-implanted samples were improved. However, in order to activate an implanted B ion, B-implanted samples needed an annealing of above 1000 °C. The implied Voc of lifetime samples by quasi-steady-state photoconductance decay followed the trend of diode properties on annealing temperature. Finally, IBC cell was fabricated with a two-step annealing at 1050 °C for B of the emitter and 950 °C for P of the front and back surface fields. The IBC cell had Voc of 618 mV, Jsc of 35.1 mA/cm2, FF of 78.8%, and the efficiency of 17.1% without surface texturing.

The effects of 200 °C post-annealing and 85 °C and 85% relative humidity temperature and humidity (T/H) treatments on the interfacial adhesion energy of a Cu/SiN x interface were systematically investigated. The results of a four-point bending test, X-ray photoemission spectroscopy, and high-resolution transmission electron microscopy revealed that the interfacial adhesion energy during T/H treatment decreased with time faster than during annealing treatment, which is closely related to the faster Cu oxidation of SiN x /Cu interfaces.

P-type and n-type wafers were implanted with phosphorus and boron, respectively, for emitter formation and were annealed subsequently at 950∼1050∘Cfor 30∼90 min for activation. Boron emitters were activated at1000∘Cor higher, while phosphorus emitters were activated at950∘C. QSSPC measurements show that the impliedVocof boron emitters increases about 15 mV and theJ01decreases by deep junction annealing even after the activation due to the reduced recombination in the emitter. However, for phosphorus emitters the impliedVocdecreases from 622 mV to 560 mV and theJ01increases with deep junction annealing. This is due to the abrupt decrease in the bulk lifetime of the p-type wafer itself from 178 μs to 14 μs. PC1D simulation based on these results shows that, for p-type implanted solar cells, increasing the annealing temperature and time abruptly decreases the efficiency (Δηabs=−1.3%), while, for n-type implanted solar cells, deep junction annealing increases the efficiency andVoc, especially (Δηabs=+0.4%) for backside emitter solar cells.

A nanoelectromechanical (NEM) switching device is developed with a new technique involving a liquid medium. Operation voltage is reduced by about 40% and the number of switching cycles with reliable device performance is improved dramatically, more than 5-fold. The device has a 50 nm thick TiN cantilever with a 40 nm air-gap. A CMOS compatible process is employed.

The effect of post-chemical–mechanical polishing (CMP) surface treatments on the interfacial adhesion energies between electroplated Cu thin film and SiN x capping layer was evaluated using a four-point bending test. The polished Cu surface was treated by one of three methods: no surface treatment, cleaning by plasma with a vacuum break, and cleaning by the wet chemical method. X-ray photoemission spectroscopy (XPS) analysis on the delaminated interfaces, cross-sectional high-resolution transmission electron microscopy (HR-TEM), and also the electron energy loss spectroscopy (EELS) analysis were performed on the interfaces. The interfacial adhesion energy increases with post-CMP cleaning, which is strongly influenced by the effective removal of residual oxygen at the Cu surfaces.