Clean room equipment
- Measurement Suite
- Metal Deposition
- Yellow Area (Photolithography)
- Wafer Microscope
- Rapid Thermal Annealing system
The Measurement Suite consists of a number of Keithley instruments controlled via a pc computer running Labview software and a manual wafer probe station with six probes. The following instruments are included:
- 236 Source measure unit
- 2410 HV Digital Sourcemeter
- 2420 HC Digital Sourcemeter
- 590 CV Analyser
- 2361 Trigger control unit
- 7001 80 CH Switching system with installed 7065 Hall Effect Card.
Initially users must anticipate creating their own Labview programs in order to make measurements. With the passage of time a suite of programs will thus be created.
The metal deposition facility consists of two machines. The Eurocoater thermal evaporator and the EBS-1800 e-beam deposition equipment. The e-beam evaporator is also capable of dielectric deposition as well as metals.
Both systems have identical pumping systems. The roughing pumps are Telstar 35 m3 /hr rotary pumps while the main capability is provided by CTI-8 cryopump pumping the system through a high conductance gate valve. The base pressure of both systems, when clean, is 3 x 10-8 Torr and the vacuum can be held in the mid 10-7 regime during deposition if proper procedures are followed.
The deposition source for the Eurocoater thermal evaporator is a three kilowatt transformer which has a maximum supply capability of 600 A at 5 V. The source metal to be evaporated is placed in a suitable refractory boat or hearth. The deposition source for the EBS-1800 system is a four hearth electron beam gun with 7 cc pockets powered from a 10 kV power supply.
Although there are a number of panels in the control rack for operation of the various sub-system components of the equipment, primary control is via a Maxtek MDC-360 Deposition Controller for both the Eurocoater and EBS-1800 systems. Following some experimentation, calibration and simple loading of parameters into the MDC-360 it is feasible to operate the deposition process in both systems by 'single-button' operation.
The Eurocoater Thermal evaporator has a planetary carousel substrate holder designed for eighteen 3'' diameter wafers with two motion rotation. The EBS-1800 e-beam evaporator has a carousel holder for twelve 4'' wafers.
For other samples users must anticipate making a suitable jig to hold their samples. It is best designed around the existing holders; thus for the thermal evaporator a location nest machined into a 3'' diameter disc is optimum and for the e-beam system, similar, but using a 4'' diameter aluminium disc.
Yellow Area (Photolithography)
A custom designed yellow area of 18 sq. meter area is set aside for the photolithographic process. This part of the facility contains all tools needed for photolithography. An environmentally controlled chemical work station for spinning on photo resist; an extracted booth containing hotplates for resist baking and a Quintel mask aligner for aligning and exposing of resist patterns.
The Quintel Q4000-6 Mask Aligner has three interchangeable substrate tools with a maximum substrate size of 6'' diameter. It has a manual tray load with PLC electronic controller. Alignment is achieved with a manual X-Y joystick alignment stage. There are three printing modes; soft/pressure or vacuum contact. The 365 nm. UV exposure optics contains a 350-watt lamp powered from a Vari Watt Power Supply.
Viewing is either through the split field microscope or through the CCTV camera system, which also offers single or split field viewing. Resolution is one micron.
An Oxford Instruments Plasmalab 80+ RIE is configured for reactive ion etching, primarily of the dielectric films deposited in the other apparatus namely silicon dioxide, silicon nitride or silicon oxynitride. The system is pumped by a 4000 l/s turbo pump backed by a rotary pump. The lower electrode upon which the substrate is placed is 240 mm diameter and will comfortably accommodate a single 6'' diameter wafer. A single 500 Watt 13.56 MHz RF generator supplies the RF power for the etching process. The etching process is generally carried out at a substrate temperature near to 20 degree C, thus allowing photoresist masking to be used. Process control during deposition is through a pc computer running Windows based custom software.
An Oxford Instruments Plasmalab 80 + PECVD is configured for deposition of dielectric films, namely silicon dioxide, silicon nitride or silicon oxynitride. The system is pumped by a roots/rotary combination pump set. The lower electrode upon which the substrate is placed is 240 mm diameter and will comfortably accommodate a single 6'' diameter wafer. Two RF generators supply the RF power during deposition, one at 90 kHz and the other at 13.56 MHz with a frequency mixing filter enabling near zero stress films to be deposited on sensitive samples. Films are generally deposited at a substrate temperature near to 350 degree C. Process control during deposition is through a pc computer running Windows based custom software.
The cleanroom facility contains an Olympus BX51 reflective microscope with 5X, 10X, 20X, 50X, 100X objectives. The microscope has an Olympus Digital camera attached on the trinocular head. Images can be collected directly on the camera and/or downloaded onto the associated pc computer for transmission by e-mail or ftp
Rapid Thermal Annealing System
The Jipelec Jetfirst Rapid Thermal Annealing Processor will process up to 4'' diameter wafers one at a time up to a temperature of 1000 degree C with heating and cooling rates up to 300 degree per second depending on the thermal mass of the sample. Heating is achieved by a bank of twelve lamps in two zones with a maximum power output of 30 kVA. Temperature monitoring and control is by K type thermocouple or Ircon modline 4-47, wavelength 4.8-5.2 micron, pyrometer with a range of 100 to 1000 degree C.
As configured the annealing process can be carried out in vacuum provided by a rotary pump only or in nitrogen gas. Process control is through a pc computer running custom software. Users must expect to carry out some programming and calibration.