Simulationskonzept für 32 nm CMOS Technologien:
Modellierung, Simulation und Charakterisierung des CMP-Planarisierungsverhaltens von dielektrischen Materialien

Sponsor:
BMBF-Projekt /Förderkennzeichen: 01M3183B/13N10808

Founded project partners:
- Institut für Halbleiter- und Mikrosystemtechnik (IHM) Technische Universität Dresden
- Fraunhofer-Center Nanoelektronische Technologien (CNT), Dresden
- Leibniz-Institut für Polymerforschung Dresden e. V. (IPF)

Coworkers:
Dr. Cornelia Bellmann

Duration:
06/2007 - 12/2010

Abstract:
Economy and steadily decreasing structure sizes force to higher efficiency during the qualification and optimization of the chemical mechanical planarization (CMP) of structures within the semiconductor fabrication process. Hence, the duration of optimization cycles has to be shortened drastically using modelling approaches verified with representative experiments and measurement data. Since theory and experience don’t provide stringent approaches to solve this task, the project targets to the bottom up elucidation of the principal polishing mechanisms in example of oxide polish starting at the particle via the structure to the chip level. Under the modular comprehension of all CMP-relevant partial elements: polishing dispersion (slurry), polishing pad and special chip layouts, modelling processes have been developed to investigate their interaction. Novel methods and techniques for in situ characterization of the interactions of pad, wafer and the nanodispersive system slurry, together with empirical results from polishing experiments are included into this process. The techniques and consumables developed and used for thecharacterization of CMP relevant physical and chemical interrelations, i. e. the microstructured single reflection elements Si wafers with oxide layers, as well as force distance measurements with AFM cantilever tips having the dimension of a single particle in contact with surfaces, have been shown to be potentially beneficial for a series of similar investigation topics in other research areas. The extended understanding of the colloidal interactions of the nanoparticles within the polishing slurries and with the wafer and pad surface in dependence of their pH-values and ionic strengths was verified by cryo-TEM images and a model of potential formation. Within the dimensions of the structure and chip level planarization, the “Global Heights model” developed in the course of the project shows good compliance with experimental results and has bee tested for the case of practical CMP topics and the planarization modelling of real product layouts at GLOBALFOUNDRIES. Supplementary investigations considering the influenceof the pad properties and the conditioning process on the planarization behaviour provide a more complex understanding of the pad-wafer interactions in CMP.