The S3-8 10 µm substrate tester is the latest model of a new atg Luther & Maelzer product line launched last year with the introduction of the single sided S3. The single sided S3 and the double sided S3-8 both meet the challenging requirements of high end substrate test such as positioning accuracy and high number of contact points by applying the advanced flying probe technology of atg Luther & Maelzer.
Substrates are used to enable a connection between a semiconductor and a printed circuit board. A typical test panel consists of about 50 to 100 single substrates and has a size of approximately 250 mm x 80 mm. Each substrate has about 1000 to 2000 test points requiring about 100,000 pads being contacted to achieve 100% continuity and isolation testing. For testing substrates on semiconductor side, structures as small as 10 µm have to be reliably contacted.
To meet this challenge the S3-8 utilizes eight freely moveable test heads and achieves a test rate of 100 ohmic two-point measurements per second. Optionally the test system can be fitted with a vacuum table for a capacitance based test.
Prior to electrical test, an optical alignment of the test sample correlates the shrinkage and offset of the finished product with the testing data and adjusts
automatically. Two 5 Megapixel color cameras with a resolution of 1.2 µm ensure positioning accuracy of +/- 1.5 µ. The S3 systems work with a micro needle with a contacting pressure that is programmable from 0.3 g up to 2.5 g to ensure best test yield and repeatability without damaging the contact pads. The maximum test area of the substrate tester S3-8 is 350 mm x 310 mm.