Patterning issues for the fabrication of sub-micron memory capacitors' electrodes
This paper describes some of the key issues associated with the patterning of metal electrodes of sub-micron (especially at the critical dimension (CD) of 0.15 μm) dynamic random access memory devices. Due to reactive ion etching lag, the Pt etch rate decreased drastically below the CD of 0.20 μm and thus K-th storage node electrode with the CD of 0.15 μm could not be fabricated using the Pt electrodes. Accordingly, we have proposed novel techniques to surmountly-the above difficulties. The Ru electrode cannot for the stack-type structure is introduced and alternative multischemes based on the introduction of the concave-type selfstructure upto using semi-Pt or Ru as an electrode material are outlined respectively.
Control of Etch Slope during Etching of Pt in Ar/Cl2/O2 Plasmas
Pt patterns of the 0.25 µ m design rule were etched at 20° C using a magnetically enhanced reactive ion etcher. The main problem of this device integration process is the redeposition of the etch products onto the pattern sidewall, making it difficult to reduce the pattern size. In both cases using a photoresist mask and an oxide mask, the redeposits of the etch products onto the sidewall were reduced by the addition of Cl2 to Ar, although the etch slope was lowered to 45°. Using the oxide mask, by adding O2 to the Cl-containing gas, the etch slope was increased up to 70°, and the redeposits were removed by an HCl cleaning process.
Historias de mi barrio: contemporary art in a community at high risk of social exclusion
Abstract Historias de mi barrio is a piece of pedagogic research aimed at highlighting the way art can articulate the relationship between the educational context and a neighbourhood at high risk of social exclusion. The starting point for this study was to ask whether this type of research, centred around the arts, was suitable in complex contexts and whether it might eventually lead to pedagogic improvement. The results gathered, and indeed the work carried out by the artists and university lecturers involved, together with pupils 6–12 years old and their instructors in a state school, provide evidence of a positive answer – and notably of the necessity of knowing about the socio-economic reality of the student cohort when planning learning projects and of the importance of the arts as a crucial element in education.