Parylene stiction

This paper presents a preliminary study into stiction between parylene C and substrate surfaces for biocompatible check-valve applications. During fabrication, parylene C is used as the structural material for the check-valve. The substrate surfaces studied include Au, Al, Si, parylene C, XeF_2 treated Si, and silicon dioxide. Stiction between different surfaces is created after sacrificial photoresist etching. Then, the stiction is measured using blister tests, and stiction mechanisms for different materials are investigated. The devices are released with different recipes to examine their effects. Finally, the results of the study reveal methods to control the cracking pressure of parylene check-valves

Sentinel-1 InSAR measurements of surface elevation changes over yedoma uplands on Sobo-Sise Island, Lena Delta

Yedoma is vulnerable to thawing and degradation under climate warming, which can result in lowering of surface elevations due to thaw subsidence. Quantitative knowledge about elevation changes can help us better understand the freeze-thaw processes of the active layer and yedoma deposits. In this study, we utilize C-band Sentinel-1 InSAR measurements, characterized by frequent sampling, to study the elevation changes over ice-rich yedoma uplands on Sobo-Sise Island, Lena Delta. We observe significant seasonal thaw subsidence during summer months and inter-annual elevation changes from 2016 to 2017. Here, we demonstrate the capability of Sentinel-1 to estimate elevation changes over yedoma uplands. We observe interesting patterns of stronger seasonal thaw subsidence on elevated flat yedoma uplands when compared to surrounding yedoma slopes. Inter-annual analyses from 2016 to 2017 revealed mostly positive surface elevation changes that might be caused by delayed thaw seasonal progression associated with mean annual air temperature fluctuations