Description:
An instrument and method for depositing thin film alloys over large areas under vacuum. The key features stem from the use of close-space sublimation sources with independent valve and temperature control.
At a Glance
- Thin film deposition of complex alloys onto large area substrates
- Scalable, fast, and able to deposit alloyed films of graded composition over the film thickness
- Reduces production costs and increases design flexibility of thin film devices
- Useful for advanced photovoltaic modules and for many other thin film technologies
Detailed Description
This innovation is a process and hardware by which deposition of large-area alloy thin films is possible with varied material properties throughout the thickness. The hardware is a close-space sublimation (CSS) sources with an added valve-controlled and thermally independent vapor feed. For example, the added vapor feed could be another sublimation source that is valved by a mechanical shutter. The added vapor feed allows alloying and/or doping of the grown film during deposition and can be adjusted continuously during the deposition to form graded films.
The setup is scalable to large areas and is usable for many alloys and dopings. For example, a ternary alloy of Cd1-xMgxTe can be made by feeding Mg vapor to a CdTe CSS deposition source. Many other material combinations are possible for growth of thin films for a wide variety of applications. This inventions enables complex alloys and materials to be deposited in one step at high deposition rates over large areas, thus reducing costs of production and increasing design flexibility in thin-film applications.
This innovation is part of a large portfolio of thin film technologies specifically developed for CdTe photovoltaic devices but potentially applicable to a wide variety of thin film technologies. Thin film coated substrates are ubiquitous in today's society and have been used for numerous aspects of consumer electronics (from integrated circuit fabrication to cell phone, computer and television display coatings), optics (e.g., coating glass), microparticle fabrication, photovoltaic fabrication, and packaging (e.g., aluminum coating on plastic for potato chip bags).
