Polishing damages to electrical properties of BLT thin film capacitors fabricated by damascene process of chemical mechanical polishing
BLT thin film capacitor was fabricated by the novel method of chemical mechanical polishing (CMP) process. The electrical characteristics including P-V and I-V of BLT capacitor were damaged by the polishing pressure which is one of the main factors to improve the CMP performance for BLT thin film; therefore, the lower polishing pressure must be selected for the good electrical characteristics although the removal rate was lower.
Chemical Mechanical Polishing of Al and SiO2 Thin Films: The Role of Consumables
Chemical mechanical polishing (CMP) studies of blanket aluminum, patterned aluminum, and SiO 2 thin films using a commercial slurry based on Al 2 O 3 abrasive particles are presented. Both silicon dioxide and aluminum blanket films were polished with two pads of different hardness and structure. The removal rate and the dependence of the removal rate on pressure and linear velocity for both materials varies significantly with pad type. For the softer pad, the Al removal rate depends critically on the surface saturation of the pad with Al 2 O 3 slurry particles. Scanning electron microscopy and X-ray photoelectron spectroscopy were used to study the texture and chemical composition of the soft pad after different polishing conditions. We found saturation of the pad surface with Al 2 O 3 particles but no metallic aluminum on the pad after CMP. Pad reconditioning causes the removal of the abrasive particles from the pad surface. Patterned aluminum samples with a TiN barrier layer were polished in alumina slurry with and without hydrogen peroxide using the soft pad. During CMP of microstructures, both Al and TiN must be removed at similar rates. The removal rate of the TiN film is dramatically enhanced when H 2 O 2 is incorporated into the slurry, whereas polishing of aluminum thin films showed that the oxidizer has no effect on the Al removal rate. Passive soaking of TiN in H 2 O 2 slurry revealed that TiN readily dissolves in the presence of a strong oxidizer, which increases the chemical component of the CMP process.
Using Skills from Art in Surgical Practice and Research-Surgery and Art
Many aspects of surgery and the arts are inexorably linked together, and the use of artistic techniques or ideas to improve surgical practice is present throughout the history of medicine. In all forms of surgery, throughout the ages, artists have been used to illustrate new ideas, new techniques and to document surgical practice. Some of the most successful art originated from surgeons who were also artists; perhaps due to their innate understanding of what they were portraying. Studying art and developing creative skills can enhance modern surgical practice in many different ways.