Bernhard Neureither

Tungsten Chemical Mechanical Polishing

After chemical mechanical polishing (CMP) of oxides became a standard method for global planarization, the polishing of metals is now being embraced by manufacturing. Although tungsten CMP has been used for subhalf-micron technologies for quite some time, there is still a lack of theoretical understanding and modeling of the metal CMP processes. This paper presents a mathematical approach to describe erosion and dishing for tungsten CMP. The model, which represents the pad by a network of springs, simulates the profile of a dished tungsten line. The calculated data are then compared with experimental data.

Boron Nitride and Silicon Boron Nitride Film and Polish Characterization

A (silicon) boron nitride deposition process based on diborane and ammonia chemistry has been developed. Stable (silicon) boron nitride films have been obtained and the film properties were characterized. The mechanical resistance of boron nitride films against abrasives is utilized for stop layer applications for chemical mechanical polishing. The effectiveness of stop layers can be enhanced by end point detection systems. Two different systems will be discussed.

High Selectivity Magnetically Enhanced Reactive Ion Etching of Boron Nitride Films

Oxygen and tetrafluorocarbon magnetically enhanced reactive ion etching (MERIE) of plasma chemical vapor deposited (CVD) boron nitride (BN) and silicon boron nitride (SiBN) was studied for both blanket and submicron patterned films. The relative etch selectivities of the BN and SiBN to oxide (SiO 2 ) and nitride (SiN) were determined. In general, oxygen-rich O 2 /CF 4 MERIE produce very high etch selectivity results while maintaining vertical etch profiles. This etch process expands the potential for use of BN/SiBN in fabrication of subhalf micron devices

High-selectivity magnetically enhanced reactive ion etching of boron nitride films

Oxygen and tetrafluorocarbon magnetically enhanced reactive ion etching (MERIE) of plasma chemical vapor deposited boron nitride (BN) and silicon boron nitride (SiBN) was studied for both blanket and submicron patterned films. The relative etch selectivities of the BN and SiBN to oxide and nitride were determined. In general, oxygen-rich O2/CF4 MERIE produce very high etch selectivity results while maintaining vertical etch profiles. This etch process expands the potential for use of BN/SiBN in fabrication of sub-half micron devices.

Low stress oxide/nitride passivation topography and influence on electrical devices

A new low-stress oxide/nitride sandwich passivation using layers of plasma-enhanced chemical vapor deposition (PECVD) TEOS and PECVD Si/sub x/N/sub y/H/sub z/ that achieves high device lifetimes is presented. A nonplanarized low-stress sandwich as well as a planarized one are investigated. The planarization includes deposition and in-situ etching of the TEOS-based PECVD oxide. Scanning electron microscopy (SEM) analysis of narrow metal 2 spaces and via holes show a conformal oxide/nitride deposition and local planarization of the oxide without voids, respectively. In the case of the nonplanarized passivation variation, as compared to the passivation sandwich with high stress, the lifetimes of three different NMOS devices are increased by a factor of 3-4.<<ETX>>