Showing papers by "Kamaljit Rangra published in 2013"
12 May 2013
Abstract: Electroplated copper thin films have been extensively used for interconnections in semiconductor devices. In this paper, electroplating of copper has been investigated to study the dependency of plated film thickness, current efficiency and sheet resistivity on current density. Copper film is electroplated on gold seed layer for via filling using different current densities varying from 10mA/cm to 70mA/cm at constant temperature (40°C). Annealing analysis for plated thick film is done at 200°C for 30 minutes. Surface roughness reduces along with resistivity with annealing.
1 citations
01 Jan 2013
TL;DR: In this article, the effect of speed and ramp on the thickness of photoresist was analyzed with a set of experiments and the results showed that the spin speed and the ramp effect affects thickness and uniformity respectively.
Abstract: Thick photoresist applications have been a key field of interest in recent years for fabrication of microstructures. Besides bump fabrication and wire interconnect technology, the method of patterning thick layer photoresist by UV lithography is specially developed for MEMS applications. In this paper, a new photoresist AZ9260 (commercially available) is optimized for various thicknesses and the effect of speed and ramp on the thickness is analyzed with a set of experiments. Thickness of 6 μm, 9.8 μm, and 14 μm has been optimized with a smooth surface profile at a ramp of 5000 rpm/sec. The spin speed and ramp affects thickness and uniformity respectively. The standard deviation for lower and higher ramp is 0.8500 and 0.0933 respectively. Prebaking and exposure times are also optimized. The exposure time is 20 sec and developing time is 130 sec.