This is a commercial MBE system with a few customizations that PI has purchased from Omicron, Germany. It consists of a UHV (< 10‐10 Torr) growth chamber, a UHV buffer chamber and a high vacuum load lock chamber. The main chamber has a cyro-pump (CP-8) and a magnetically levitated turbomolecular pump with a pumping speed of 2100 l/s allowing for ultra low-pressure ideal atmosphere for high purity growth. The main growth chamber has nine effusion cell ports, equipped with two three temperature effusion cells (< 2200 °C), two medium temperature effusion cells (<1100 °C), three low temperature gas sources and an auto-tuned rf plasma source for oxygen. The main chamber has an oxygen compatible SiC heater stage (up to 1200 °C in POx = 1×10-5 Torr), a reflection high-energy electron diffraction set-up (RHEED), a residual gas analyzer (RGA), a quartz crystal monitor (QCM) mounted on a retractable rod in a load lock assembly allowing for easy replacement of crystals. The buffer chamber is set up for sample cleaning and annealing up to 1300 °C and can store five samples at a time for growth.
Dual MBE Systems
This system is equipped with two full-size EVO-50 MBE system connected through a buffer chamber and a load lock. Two MBE chambers have magnetically levitated turbomolecular pumps allowing for ultra low-pressure ideal atmosphere for high purity growth. Each chamber has 10 effusion cell ports. The system is also equipped with In-situ Reflection High Energy Electron Diffraction (RHEED) set up with a 15 KV electron gun, beam rocking capability, and a full-version of k-Space image acquisition and analysis software. These systems are fully operational since September 2020.
This is a home-built UHV selenide MBE system with 6 ports and a base pressure below 10-9 Torr. The system incorporates a large turbo pump, a set of effusion cells and gas sources. The selenide MBE is equipped with a load lock for loading of samples without breaking the vacuum. This system is being installed in the PI's lab.
This programmable furnace is capable of high temoerature annealing of samples under controlled gas atmosphere (oxygen, nitrogen, and forming gas). The maximum achievable temperature is 1400 °C.
Dynacool Physical Property Measurement System (PPMS)
Our lab is also equipped with a cryogen-free Quantum Design PPMS (Physical Property Measurements System) for electronic and thermal measurements of the materials. The system has the following features:
- Magnetic field range: -9 to +9 T
- Temperature range: 1.8 K - 400 K
- Resistivity option (DC transport)
- Electronic transport option (AC transport)
- Horizontal rotator probe
- Thermal transport option for Seebeck and thermal conductivity measurements
- External Keithley source measurement units (SMU's) for customized experiments such as electrostatic gating
- Impedance Analyzer for temperature- and frequency-dependent dielectric measurements
Probe Station with Impedance Analyzer
Probe station with four probes, a two-channel source measure unit, an impedance analyzer, and a ferroelectric analyzer. It will be integrated with an existing Dynacool PPMS system and a custom-made heating stage. This set up allows us for very quick measurements of room-temperature resistivity, dielectric constant vs frquency, and P-E loops. These measurements provide a critical feedback for growth optimization of thin films.
Ferroelectric Testing and Energy Conversion
This is a custom-built setup equipped with a heater stage, probes, source meters, impedance analyzer and ferroelectric tester (Radiant) for energy conversion project. These sources are computer controlled using a lab-view software for easier and faster control and recording of data.