Mechanical, Electrical And Chemical Effect Of Laser Spike Annealing On Novel Porous Low Dielectric Constant Ethyl-Bridged Organosilane
Scaling of semiconductor devices has also driven a need for the improvement of interconnects. As feature sizes became smaller, the parasitic capacitance increased between wires resulting in unacceptable interconnection delay. To mitigate this problem, low dielectric constant materials ("low k" materials) were introduced to replace the silicon dioxide, whose k value around 4 is well outside the target value of k = 2.0. While the incorporation of organic groups and, especially, the presence of pores in an Si-O framework material decreases the dielectric constant dramatically, it also leads to the loss of mechanical strength. Alternative processing technologies are required to improve mechanical properties of SiCOH-class materials, the current standard for low k materials, while maintaining dielectric properties. Laser Spike Annealing (LSA) is one alternative annealing process that may achieve this goal. This work explored the use of LSA to anneal porous low k ethyl-bridged organosilane films. This novel SiCOH-class material has the potential to meet targets with respect to lower dielectric constant and stronger mechanical properties. Use of LSA was explored to determine the behavior under several heating processes. The effects of LSA on this new low k film and a comparison of the results to those using other rapid annealing techniques were studied. In this thesis, we will discuss the structural and chemical evolution as a function of LSA and hotplate conditions. Second, we will link the dielectric and mechanical effects of LSA to those structural changes under a continuous temperature profile. Third, we will explore the effects of dwell time, initial structure and initial porosity on the LSA-generated results. Finally, we will evaluate and compare LSA and the conventional hotplate annealing.
Low k materials; LSA
Thompson, Michael Olgar
Materials Science and Engineering
M.S., Materials Science and Engineering
Master of Science
dissertation or thesis