INFRARED DETECTOR CHOICES
| Most photo-emissions from failure sites derive their energy from the semiconductor quantum bandgap. In silicon circuits the photo-emissions are primarily infrared. Some energetic electrons will produce barely visible red light, but most of the emissions are longer than 1 micron wavelength, so they are in the invisible short wave infrared wavelengths. Moreover, flip-chip construction and large numbers of metal layers mask emissions from the front of the die. In many cases it is necessary examine the chip from the back of the die or wafer. Fortunately silicon is transparent at infrared wavelengths, so it is only necessary to field an infrared detector in the emission microscope. QFI offers 2 infrared detectors. |  |
|
Back
Illuminated Silicon
For less demanding and cost sensitive applications QFI offers a scientific grade silicon detector array. Silicon cameras are cost effective for back-side inspection and very satisfying for front side inspection. QFI offers the most sensitive silicon camera available. The detector is back-thinned and back-illuminated for very high quantum efficiencies and sensitivity. Each pixel integrates signal directly to a capacitor on the cooled CCD array, which yields higher signal to noise ratios than off-chip video frame integration. Competing science grade cameras require a mechanical shutter. Our CCD uses on-chip frame transfer technology to eliminate noise and vibration and mechanical failures. QFI’s Si camera supports binning for additional sensitivity. |
 |
HgCdTe Infrared Detector For the most demanding requirements QFI offers an astronomy grade mercury-cadmium-telluride (HgCdTe) detector array. This detector is extremely sensitive from 800 nm to 1,600 nm, which is an excellent match for silicon based defect emissions and also perfect for backside wafer or die inspection. It is cryogenically cooled resulting in very low dark current and it is generally acknowledged to be the most sensitive emission microscope detector material currently available. |
 |