What are up-screened components/devices in the frame of qualification of electronic components?
How is it done?
Semiconductor components have a large spread of parameters as manufactured.
Up-Screening consists of the manufacturer testing them, and selecting devices with particular parameters. This is also called 'binning', especially in LED production, where the devices can be sorted according to colour temperature.
For instance, the BC108 transistor can be bought as a 108, or as a A, B or C group, which are selected on HFE.
Obviously, the better performing devices are sold at a premium price
Up-screening is the testing a device to a wider temperature range than the original manufacturer specified.
The only way to assure commercial temperature range devices can operate at these extended temperature ranges is to perform full AC/DC/Functional testing to “Upscreen” them for these harsher environments. See here