Refine
Document Type
- Article (2)
Language
- English (2)
Has Fulltext
- no (2)
Is part of the Bibliography
- no (2)
Keywords
- atomic force microscopy (1)
- damage (1)
- fracture strength (1)
- pattern collapse (1)
Institute
Begutachtungsstatus
- peer-reviewed (1)
Enhanced particle removal processes in wet cleaning as well as drying processes of semiconductor wafers can cause significant lateral forces on surface structures. These forces, however, must not exceed the mechanical stability of structures on the wafer. Thus, a mechanical fracture test was used to assess the lateral mechanical stability of polysilicon line structures in relevant process liquids. The mechanical test was based on nanomanipulation with an atomic force microscope. Compared to fracture tests in air, data acquired in liquid isopropanol revealed a stabilizing effect. The differences in fracture forces can be attributed to a stress corrosion process on the surface. The size of the generated damage was influenced by the viscosity of the surrounding media.
The mechanical stability of nanostructures depends on the surrounding medium. Their stability was probed by lateral force microscopy in liquid media. Previously reported data on water and isopropanol showed an increase in the fracture strength for the latter. Further tests with other alcohols (ethanol, 1-butanol) also showed an increasing strength. The interface between the liquid and the surface is the decisive factor for the influence of the media. When altering the interface with a cationic surfactant or a self-assembled monolayer, an increase of the fracture force by 100 % compared to de-ionized water could be measured.