Surfaces with high solar reflectance and high thermal emittance on structured silicon for spacecraft thermal control

Presented here is an examination of unstructured and structured (by anisotropic etching), monocrystalline silicon wafers coated with sputter deposited aluminum and chemical vapor deposited silicon dioxide for high solar reflectance and high thermal emittance, respectively. The topography of the samples was characterized with optical and scanning electron microscopy. Optical properties were examined with reflectance and transmittance spectroscopy, partly by usage of an integrating sphere. The measurement results were used to estimate the equilibrium temperature of the surfaces in space. The suitability of the surfaces with high solar reflectance and high thermal emittance to aid in the thermal control of miniaturized, highly integrated components for space applications is discussed. A silicon dioxide layer on a metal layer results in a slightly lower reflectance when compared to surfaces with only a metal layer, but might be beneficial for miniaturized space components and modules that have to dissipate internally generated heat into open space. Additionally, it is an advantage to microstructure the emitting surface for enhanced radiation of excess heat.

[1]  A. C. Tribble,et al.  UNITED STATES AND RUSSIAN THERMAL CONTROL COATING RESULTS IN LOW EARTH ORBIT , 1996 .

[2]  Claes-Goeran Granqvist Progress in solar energy materials: Examples of work at Uppsala University , 1998 .

[3]  Lars Stenmark,et al.  A large stroke, high force paraffin phase transition actuator , 2002 .

[4]  D. Jaworske Correlation of predicted and observed optical properties of multilayer thermal control coatings , 1998 .

[5]  M. Madou Fundamentals of microfabrication , 1997 .

[6]  W. Windbracke,et al.  Thermal Annealing Effects on the Mechanical Properties of Plasma‐Enhanced Chemical Vapor Deposited Silicon Oxide Films , 1992 .

[7]  R. Osiander,et al.  Microelectromechanical devices for satellite thermal control , 2004, IEEE Sensors Journal.

[8]  J. Triolo,et al.  Evaporated Ag coated with double layers of Al2O3 and silicon oxide to produce surface films with low solar absorptivity and high thermal emissivity , 1973 .

[9]  M. Green Silicon solar cells : advanced principles and practice , 1995 .

[10]  T. S. Eriksson,et al.  Infrared optical properties of silicon oxynitride films: Experimental data and theoretical interpretation , 1986 .

[11]  Craig Underwood,et al.  In-orbit results from the SNAP-1 nanosatellite and its future potential , 2002, Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[12]  James R. Wertz,et al.  Space Mission Analysis and Design , 1992 .

[13]  William T. Beauchamp,et al.  Coatings for temperature reduction in space: a case study of solar cell covers , 1994, Optics & Photonics.

[14]  Djemel Lellouchi,et al.  The advent of MEMS in space , 2003, Microelectron. Reliab..

[15]  G. Niklasson,et al.  Infrared emittance modulation of all-thin-film electrochromic devices , 2004 .

[16]  Andrew D. Ketsdever,et al.  Performance testing of a microfabricated propulsion system for nanosatellite applications , 2005 .

[17]  G Hass,et al.  Solar absorptivity and thermal emissivity of aluminum coated with silicon oxide films prepared by evaporation of silicon monoxide. , 1970, Applied optics.

[18]  Michael J. Rycroft,et al.  Smaller satellites: bigger business? : concepts, applications and markets for micro/nanosatellites in a new information world , 2002 .

[19]  D. E. Martin,et al.  Thermal management for multifunctional structures , 1999 .

[20]  A. Goetzberger,et al.  Crystalline Silicon Solar Cells , 1998 .

[21]  Gajanana C. Birur,et al.  Large, Switchable Electrochromism in the Visible Through Far‐Infrared in Conducting Polymer Devices , 2002 .

[22]  G. Niklasson,et al.  Titanium–aluminum–nitride coatings for satellite temperature control , 2000 .

[23]  Yuji Nagasaka,et al.  Total Hemispherical Emittance of Polyimide Films for Space Use in the Temperature Range from 173 to 700 K , 2002 .

[24]  C. Granqvist,et al.  Materials science for solar energy conversion systems , 1991 .

[25]  C. Ribbing,et al.  TiN-alloy coatings for temperature control of space vessels. , 1999, Applied optics.

[26]  E. Ritter,et al.  Effect of ultraviolet irradiation on the optical properties of silicon oxide films. , 1965 .

[27]  Antonio Martínez de Aragón Space applications of micro/nano-technologies , 1998 .

[28]  L. Stenmark,et al.  Development of a MOEMS sun sensor for space applications , 2005, The 13th International Conference on Solid-State Sensors, Actuators and Microsystems, 2005. Digest of Technical Papers. TRANSDUCERS '05..

[29]  J. H. Apfel Triangular coordinate graphical presentation of the optical performance of a semitransparent metal film. , 1990, Applied optics.

[30]  Anders Eriksson,et al.  Design and Modeling of a Thermally Regulated Communications Module for Nanospacecraft , 2006 .

[31]  K. Hane,et al.  Spectral control of thermal emission by periodic microstructured surfaces in the near-infrared region. , 2001, Journal of the Optical Society of America. A, Optics, image science, and vision.

[32]  A. Roos,et al.  Anomalies in integrating sphere measurements on structured samples. , 1988, Applied optics.