TFQ-5 Test Fixture for Quantum Efficiency Measurements
The 50 mm x 50 mm Vacuum Test Fixture for QE Systems is designed to hold and contact substrate based solar cells up to 54 mm x 54 mm in size. This test fixture is commonly used for 20 mm x 20 mm single- or multi-crystalline silicon solar cells. It is also suitable for use with other types of solar cells that have at least one electrical contact accessible from the front of the cell.
A platform with vacuum holes holds the test device and makes electrical contact to its rear surface. A micropositioner probe contacts the front surface. A vacuum pump is included.
Use with Device Types Other than Crystalline Silicon
If the device under test does not have a terminal at its rear surface, use a second probe (not included) to contact the second terminal on the front. This test fixture is not suitable for use with superstrate devices, such as amorphous silicon on glass.
Soft Contacting for Delicate Devices
Some devices can be easily sctrached by the sharp, hard needles of micropositioner probes. Micropositioner probes from PV Measurements include a soft, electrically conductive device protector that can be used with the micropositioner to prevent scratching of delicate films.
Mounting the Test Fixture
The 50 mm x 50 mm Vacuum Test Fixture for QE Systems has 6.1 mm diameter holes in its base that can be used to mount it to optical tabletops using metric M6 threaded holes on 25.0 mm grids, such as supplied with QE systems manufactured by PV Measurements, Inc. It can also be mounted on angle brackets or translation stages.
Basic Temperature Control
The vacuum stage is mounted to a water circulation plate that can be used to control the temperature of the device being tested. Plumbing fittings are provided. To use this feature, the customer must supply a water circulator with temperature control for the water. Another option is to use thermoelectric temperature control, described below.
Optional Thermoelectric Temperature Control
With the optional thermoelectric temperature control, faster responsiveness and temperature precision are acheived. The termoelectric modules act as a heat pump between the vacuum plate and the water plate. The water plate acts as a thermal reservoir for the thermoelectric modules. Two temperature ranges are available: The standard temperature control range allows control between 5 °C and 60 °C. The optional high temperature range allows the temperature of the test device to be raised up to 125 °C. These options include a water chiller. No external water connections are necessary.
|Vacuum Pump Electricity||0.5 A, 115 VAC or 0.25 A, 250 VAC 50/60 Hz|
|Water Plate Flow Rate||0.5 l/min|
|Optional Standard Range Thermoelectric
Temperature Controller And Water Chiller
|8 A, 115 VAC or 6 A, 250 VAC 50/60 Hz|
|Optional Extended Range Thermoelectric Temperature Controller And Water Chiller||8 A, 115 VAC or 6 A, 250 VAC 50/60 Hz|
|Electrical Interface||2 wire|
|Front Electrical Device Connection||Joystick micromanipulator probe, 1 included (additional probes optional)|
|Back Electrical Device Connection||Aluminum vacuum chuck|
|Temperature Sensor||LM335 embedded in vacuum plate|
|Temperature Sensor||Accuracy ± 0.5 °C|
|Standard Range Thermoelectric Temperature Control||5 °C to 60 °C|
|Extended Range Thermoelectric Temperature Control||5 °C to 125 °C|
|Maximum Cell Size||50 mm x 50 mm|
|Minimum Cell Size||5 mm x 5 mm|
|Cell Style||Substrate device (at least one front contact)|
|Soft Contact||Conductive rubber|
Compatible Device Structures
Insulating Substrate Device
Conducting Substrate Device
Traditional Bulk Device
Contact your PV Measurements representative for more details on test fixtures and which one is the best for your application.