Electromagnetic Levitator Batch 2 - Investigation of Thermophysical Properties of Liquid Semiconductors in the Melt and in the Undercooled State under Microgravity Conditions (EML Batch 2 - SEMITHERM) - 01.25.17

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
The SEMITHERM experiment takes a closer look at a material that made mobile technology ubiquitous: silicon–germanium (Si-Ge) semiconductors. These computer chips are found in almost all smartphones, and creating the chips requires forming the alloy at specific temperatures. SEMITHERM is set to investigate the underlying properties of a mix of silicon and germanium as it melts in microgravity to see how microgravity affects the results.
Science Results for Everyone
Information Pending

The following content was provided by K. Sawmer, and is maintained in a database by the ISS Program Science Office.
Information provided courtesy of the Erasmus Experiment Archive.
Experiment Details

OpNom:

Principal Investigator(s)
K. Sawmer, Germany

Co-Investigator(s)/Collaborator(s)
B. Damaschke, Germany
I. Egry, Germany
G. Lohöfer, Germany
E. Ricci, Italy
E. Arato, Italy
T. Hibiya, Japan
Masahito Watanabe, Ph.D., Gakushuin University, Japan
Shunpei Ozawa, Ph.D., Chiba Institute of Technology, Narashino, Japan
Takao Tsukada, Tohoku University, Japan
N. Abrosimov, Germany

Developer(s)
European Space Agency (ESA), Noordwijk, Netherlands

Sponsoring Space Agency
European Space Agency (ESA)

Sponsoring Organization
European Space Agency

Research Benefits
Earth Benefits

ISS Expedition Duration
September 2016 - February 2017

Expeditions Assigned
49/50

Previous Missions
Information Pending

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Experiment Description

Research Overview
The SEMITHERM experiment measures the thermophysical properties of liquid semiconductor alloy Silicon-Germanium (Si-Ge), as a function of temperature.

Description
Information Pending

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Applications

Space Applications
Industry partners to the projects are seeking to optimize ground processes, and have a direct interest in the knowledge that is gained from the experiments. This can, in turn, find its way into the development of new light-weight, high-performance structural materials for space applications.

Earth Applications
Investigations carried out with the Electromagnetic Levitator (EML) provide both reference data on thermophysical properties and microstructure formation for the same metallic alloy samples. (The microstructure in an alloy influences its characteristic properties such as strength, flexibility and resistance to fatigue). This information is of importance for feeding accurate data into current numerical models on one side, and also testing these models aiming to predict the solidification profile and related microstructure formation in the alloy samples. This concerns structural steels, magnetic materials, intermetallic materials, glass forming metallic alloys etc.

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Operations

Operational Requirements and Protocols

Hardware required is the EML, including:  Experiment Module, Experiment Control Electronics and High-Speed Camera Operating System, Levitation Power Supply and Water Cooling Module, Gas Supply Module, and Sample Chamber.
 
Four out of 23 samples in Sample Container used for experiment:
  1. Si25Ge75 (doped) (ID#30) (sample sharing with NEQUISOL and NASA QUASI projects)
  2. Si75Ge25 (doped) (ID#31) (sample sharing with NEQUISOL and NASA QUASI projects)
  3. Ge (ID#16) (sample sharing with NEQUISOL and NASA QUASI projects)
  4. Si50Ge50 (ID#17) (sample sharing with NEQUISOL and NASA QUASI projects)
General:  1 run per sample with 11 different melting cycles.
 
For samples with ID# 30, 31 and 17:  precision measurements of thermal expansion, surface tension and viscosity in the stable liquid and the undercooled liquid.  Eleven cycles for thermal expansion, surface tension and viscosity to obtain enough data points, to reduce scatter of data.
 
For sample with ID#16:  precision measurements of thermal expansion, surface tension and viscosity in the stable liquid and the undercooled liquid. Three cycles for thermal expansion, 8 cycles for surface tension and viscosity to obtain enough data points, to reduce scatter of data.
 
Samples to be returned:
  1. Ge
  2. Si50Ge50.

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Decadal Survey Recommendations

Information Pending

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Results/More Information

Information Pending

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Related Websites
Electromagnetic Levitator from ESA

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Imagery