Possible, that it will be one of the two, yes. But technically, there are a few more "semiconductor manufacturers", such as X-Fab (who have been reported recently to expand their site in Dresden). Their chips are in many a car sold in Europe.
By the way, in Dresden, interest in semiconductors goes back decades. These days, there is also i.e. Globalfoundries, Infineon Technologies, NXP Semiconductors, and Renesas Electronics. (Particularly foundries as such, but may be expanding.)
As for H+E, they recently installed a "high-end ultrapure water plant for the treatment of well water for a notable semiconductor producer in Central Europe", and made a presentation about it:
https://www.he-water.group/files/co...or-the-Semi-Conductor-Industry_07-2022_EN.pdf