Papers by Keyword: Aerosol Spraying

Abstract: As the dimensions of the structures of integrated circuits shrink, the influence of particles on device yield becomes increasingly important. According to the cleaning requirements of the International Technology Roadmap for Semiconductors (ITRS) in 2007, particles of 32 nm and larger are believed to be detrimental to devices and thus have to be removed. To remove nano-particles with minimal substrate loss and no damage requires very dilute chemistries and sufficiently gentle physical forces in a cleaning process. In this work the performance of an aerosol spray based cleaning technique is evaluated with regard to the removal efficiency of nano-particles as well as substrate loss and structural damage.

Abstract: Cleaning of nano-particles is becoming a major challenge in semiconductor manufacturing as efficient particle removal must be achieved without substrate loss and without damage to fragile structures. In this work cleaning performance and structural damage by a mixed fluid-jet technique were evaluated and directly compared to the performance of several megasonic systems. The test vehicles were hydrophilic Si wafers contaminated with 78-nm SiO2 particles and 70-nm poly-gatestack line patterned wafers. The results showed a broader process window for particle removal without damaging for the mixed fluid-jet technique compared to the megasonic systems.

Abstract: With the continuous shrinkage of critical sizes in semiconductor manufacturing, nano-particles smaller than 100-nm are becoming a potential threat to devices in chips. Storage of wafers contaminated during process steps often results in a decrease of particle removal efficiency in subsequent clean, a phenomenon referred to as aging. In this work, the influence of aging on the removal of silica and silicon nitride nano-particles from hydrophilic Si wafers was studied for different storage conditions. Trends observed for aging as a function of particle size and for different tools indicated that aging will become an issue for critical cleans where substrate etching must be kept very low and the physical component of the clean must be decreased to prevent damage to fine structures. Controlling the relative humidity during storage helped in lowering the effect of aging.