A study on degradation of germanium coating on Kapton used for spacecraft sunshield application. (December 2015)

• Record Type: Journal Article
• Authors: Esther, A. Carmel Mary; Dey, Arjun; Sridhara, N.; Yougandar, B.; Bera, Parthasarathi; Anandan, Chinnasamy; Rangappa, Dinesh; Sharma, Anand Kumar
• Is Part Of: Surface and interface analysis. Volume 47:Number 13(2015)
• Page Start: 1155
• Page End: 1160
• Publication Date: 2015-12
• Subjects: germanium‐coated black Kapton -- thermal control -- RF losses -- antenna sunshield -- degradation -- XPS; Surfaces (Physics) -- Periodicals; Surface chemistry -- Periodicals; Thin films -- Periodicals; 541.33
• DOI: 10.1002/sia.5867
• Languages: English
• ISSNs: 0142-2421

Abstract

Abstract : Sunshield membranes made of germanium‐coated black polyimide (GBP) or Kapton are often used on the reflector/transmitter antenna of satellites for thermal control applications. However, the germanium top layer is prone to degrade during ground storage and implementation. Hence, vacuum/inert gas‐sealed packaging is required for storing the membranes, followed by a staggered fabrication schedule as the shelf‐life of the GBP is identified as only ~6 months. In the present study, microstructural, thermo‐optical, and electrical properties along with X‐ray photoelectron spectroscopy (XPS) studies for evaluating oxidation states of the as‐received and degraded GBP films have been investigated thoroughly. The radio frequency (RF) loss behavior of both the films has also been studied for S band (2.5–3.5 GHz), Ku band (10.5–14.5 GHz), and Ka band (30–35 GHz). Copyright © 2015 John Wiley & Sons, Ltd.