Actually there is a lot of current semi activity in Dresden. It's the biggest cluster in Europe.

Notable fabs in Dresden: Globalfoundries, Infineon, Bosch (recently opened), X-Fab, First Sensor, Plastic Logic (now defunct). May be noteworthy that some of these fabs are among the semi fabs with the highest degree of automotation world wide.

Add to this many bigger and smaller suppliers, universities, reasearch institutes and so on.

https://www.silicon-saxony.de/nc/en/members/sorted-by-alphab...

There are also plenty of Fabs in other parts of Germany: Infineon, Bosch, Nexperia, TDK, Osram, TI, X-Fab, Vishay, Elmos and some I forgot probably.

There are also many design companies. Especially noteworthy is probably Apples modem team that keep growing and growing...

CERN certainly stimulates some semi research, but it is rather specialized.