The PLD/MBE 2100 system is the smallest of the three PLD/MBE 2000 series systems yet includes all the key features of these systems. It is based around a 304L SS cylindrical chamber that is 16 inches in diameter and 18 inches high.
The chamber has a top flange that seals against the cylinder by a Viton O-ring. For UHV applications, a pair of differentially pumped Viton O-rings is provided. An electric hoist is provided to lift the top flange and allow easy access to the internal parts of the chamber.
The chamber includes one 6” CF flange for the addition of a sputter, atom, or ion source, etc. The chamber includes a number of flanges for viewing the target, substrate, and ablation plume, as well as additional accessories such as HP RHEED, emission spectroscopy, pyrometry, residual gas analyzers, etc.
Inside a PLD/MBE 2100 with a 2-inch magnetron sputter source and six-position target carousel
The PLD/MBE deposition system comes with a wide variety of options, including:
The rear of the chamber is fitted with one angled 6-inch CF port for the addition of an atom or ion source, effusion cell, or magnetron sputter source. The PLD/MBE 2100 chamber includes an internal light to provide excellent viewing of samples, target, and substrate transfers via our optional dual-wafer load lock. The walls of the chamber have a set of internal SS shields that can be easily removed for cleaning when ablated material build-up becomes significant. Furthermore, the PLD/MBE system's turbo pump mounts to the side of the chamber, protecting the pump from small parts or samples that may be dropped inadvertently into the system.
The system includes a VAT Series 642 closed-loop gate valve with an integrated pressure controller to provide rock-steady deposition pressures from 1 to 500 mTorr. The PLD/MBE 2100 system includes a Pfeiffer HiPace 400 turbo pump backed by a dry scroll pump. Standard systems include a single MKS digital MFC, and additional MFCs are easily added as needed. Vacuum gauging includes a Bayard Alpert ion gauge, two Convectron gauges, and a capacitance manometer. The base pressure of the system is 5 x 10-7 Torr standard, 5 x 10-8 Torr with optional load lock, and below 5 x 10-9 Torr with optional UHV package.
PLD/MBE 2100 Pump down curve versus time. A pressure of below 5 x 10-7 Torr is reached in about 120 minutes
All PLD/MBE systems come with a complete optical train, with kinematic mirror mounts and programmable laser beam rastering. Laser beam rastering, developed by Dr. Greer in 1987, provides excellent film thickness and target utilization. The optical trains are enclosed in laser-safe enclosures with a hinged door with laser interlock. It includes a pneumatic actuator that will open and close the excimer laser shutter via computer control. All chamber viewports include true UV grade blocking viewport covers for laser safety.
The PLD/MBE 2100 chamber is mounted on a steel support frame with an integrated optical train. A second frame is provided that includes a pair of standard 19-inch wide electronic racks, which house all the system electronics. This frame also serves as the support table for the excimer laser, providing a compact layout. Other types of lasers can be accommodated as well. With the laser located on top of the racks, it is readily accessible for service when required.
The PLD/MBE 2100 comes with a target manipulator that handles six 2-inch diameter targets. Targets are held in pedestals by gravity, so target clamping or silver paste is not required. Smaller 1-inch diameter targets or other small target sizes can easily be accommodated with optional inserts. The target manipulator is based on a pair of Ferro fluidic rotary feedthroughs that provide programmable target rotation speeds up to 50 RPM, programmable target indexing, and target toggling for enhanced use of target material. These robust Ferro fluidic sealed feedthroughs provide extended lifetime when compared with bellows-sealed based target manipulators that fail due to fatigue of the bellows due to constant target motion and indexing. All the targets are covered by a water-cooled plate with a slot that exposes the laser beam to the active ablation target.
The optical train also includes a PVD Products Intelligent Window developed by Dr. Greer in the early 1990’s. It includes a high quality AR coated window (usually for 248 nm (KrF)) for the beam to enter the vacuum chamber. An internal UV grade fused silica disc 100 mm in diameter is housed in a pair of flanges mounted on the PLD/MBE-2100. An aperture is positioned on the target side of the disc. This defines a section of the disc that allows laser radiation to pass down to the targets and the area of the disc that will collect stray ablated target material. When the local section of the disc becomes sufficiently coated with ablated target material, the disc can be easily rotated to a clean location to increase the fluence on the target. The discs are easily cleaned, and a spare disc is included. Besides keeping the window clean for extended periods of time, it also allows the user to insert a beam splitter in the path of the laser beam to reflect the laser radiation out of the chamber to a joule meter. This way, the energy that has traversed the entire optical train can be measured and adjusted to provide accurate and reproducible results from run to run. This approach to handling the laser entrance window coating is much more effective than swapping out the window every two or three runs as required on competitors' tools.
The PLD/MBE 2100 system comes with an IR lamp based heater capable of heating silicon and other non-transparent substrates to 950°C and transparent substrates to 850°C. (Note: PVD is quoting substrate temperatures, not heating element temperatures as there is a large difference in temperature between the element and the substrate on all heaters.) The heater can handle 2-inch diameter substrates or multiple smaller samples per the customer requirements (e.g. a holder for four 1-cm square samples). Using a Ferro fluidic rotary feedthrough, substrates can be rotated via computer at rates up to 40 RPM. The heater is typically mounted to a large motorized Z-stage, providing computer-controlled target-to-substrate distances varying from about 50 to 100 mm. The open architecture of our IR lamp heater is ideal for in-situ analysis using HP RHEED, and alternative deposition sources such as magnetron sputtering, effusion cells, ozone generators, atom or ion sources, etc. One of these deposition sources can be mounted on the 6” CF flange on the PLD/MBE 2100 chamber at a time.
A PLD/MBE style non-contact substrate heater with programmable substrate rotation and pneumatic shutter assembly (optional RF bias is readily available)
A water-cooled plate sits directly above the PLD targets and includes a removable cover that will expose a single target at a time for fast target transfers through a quick-access door located on the side of the chamber. The plate includes a slot for the laser beam to raster across the active rotating target and for the plume to expand out towards the substrate. The plate is sealed via VCR fittings and is fully UHV compatible. This plate protects the other targets from cross-contamination and protects the assembly’s gears and bearings from the thermal radiation from the substrate heater.