Sample Growth
At CRANN, thin films, multi-layers, and hybrid material systems are reproducibly grown by a wide variety of techniques prior to functionalization, patterning, or other processing stages. Many more bottom up assembly techniques are deployed in the PI groups. The following film growth techniques encapsulate some of the growth strategies deployed at CRANN. They are accessed either through the Central Equipment Facility [CEF] or run by Principal Investigator research groups.
Temescal FC-2000 System
The FC-2000 is a flexible evaporation system which is equipped with a number of accessories designed to meet CRANN's wide ranging research activities. The system comprises:
- a 6-pocket electron beam evaporation source, a thermal evaporation source
- an ion source
- a substrate infrared heater and liquid nitrogen cooler
- a process gas controller and
- a fast-cycle load lock.
ATV LPCVD Furnace
The ATV low pressure chemical vapour deposition tool is used to deposit various thin films, and to achieve conformal coating. Specification applications include oxidation, annealing and carbon nanotube deposition. Additional investment will enable silicon, silicon nitride, and silicon dioxide deposition processes to be run on this tool.
Tool specification
- Ramp rate 50C/ min
- Up to 50 200mm process wafers
- Temp capability 1150C
- Low pressure applications
Molecular Beam Epitaxy [MBE]
UHV evaporation system used for high quality deposition. The M600 MBE tool is a UHV evaporation system in the research group of Prof. Igor V. Shvets.
It is designed specifically for high quality deposition or epitaxial growth of metals, oxides, superlattices, and heterojunctions. Ports are reserved for more accurate flux control using either a cross beam quadrupole mass spectrometer or atomic absorption spectroscopy. The deposition chamber is fitted with a reflection high energy electron diffraction (RHEED) system for in situ sample analysis. The MBE system is also fitted with an Oxford Scientific OSPrey Plasma Source set to operate in Atomic Mode.
Contact: Prof Igor Shvets, email ivchvets AT tcd.ie
Shamrock System
Capable of processing up to 6 inch wafers The Shamrock sputter tool is a 6 target DC/RF sputter system of the type which found wide use in Seagate research and development centres.
- It is capable of processing up to 6 inch wafers
- The system is fully automatic and has a maximum capacity of 16 wafers, and can deposit on up to 4 wafers in one process at ambient temperature due to its planetary turntable geometry
- Processing several wafers at once allows for high target efficiency while maintaining low growth rate for smoother films
- Typical deposition rates are less than 1A/s.
The system currently comprises 3 deposition chambers; Chambers A, B and C with a load lock and a robotic transfer module.`
- Chamber A of the system has 6 DC sputter guns and an ion gun for substrate cleaning.
- Chamber B has 6 DC sputter guns, 2RF sputter guns and an ion gun for plasma oxidation.
- Chamber C is an ultrahigh vacuum e-beam evaporation chamber with a low pressure sputtering source. The flexibility of the system allows for alloys of up to 6 targets to be sputtered with good compositional control.
- An in-plane magnetic field can be used during deposition to set the magnetic easy axis of spin valve and tunnel junction samples, or other thin magnetic films.
- Base pressures of the system vary from 1* 10-7 Torr (for Chamber A), to 2* 10-10 Torr (for Chamber B)
Thermal Evaporator
The organic thermal evaporator consists of two thermal sources made with tungsten filaments, a Q-pod quartz crystal monitor (QCM), a substrate holder with heating capabilities, a shutter, 3 thermocouples and an additional feed-through for injecting gas. Contamination between the two thermal sources is minimized by the installation of a stainless steel divide. The pressure in this bell jar configuration is maintained by a Pfeiffer Turbo-cube pumping system which is connected through the base plate. The pressure is monitored by a full range compact ion gauge also mounted through the base plate as well. The Q-pod QCM operating at a frequency of approximately 6MHz is controlled by an accompanying software which is connected via USB port to a personal computer (PC). A standard Wayne Kerr AP6050A power supply is used to apply large currents to the thermal sources.
Pulsed Laser Deposition
The group of Prof. J. G. Lunney [TCD school of Physics & Investigator at CRANN] was the first in Ireland to use the pulsed laser deposition (PLD) technique to make thin films. PLD is a highly flexible technique for the preparation of complex materials for research. Here the technique has been employed to make thin films of a wide range of superconducting, magnetic, semiconducting and metallic materials for several EU and nationally-funded projects, collaborating with other academics such as Prof. Coey and Prof. Blau. Prof. Lunney and co-workers have shown that it is possible to use PLD to make ultra-thin multilayer films for the fabrication of multilayer mirrors and magneto-resistive devices.
Oxford Instruments Plasmalab 800+ PECVD
Plasma Enhanced Chemical Vapour Deposition system configured for deposition of silicon oxide and silicon nitride thin films
Technical Specification
- Open load system
- 460mm driven electrode
- Up to 400C deposition
- Oxide, nitride, oxynitride deposition
Contact: Peter Gleeson, email: peter.gleeson AT intel.com