What is Soldering temperature of STM32F303 IC chip 100-pin?
The soldering temperature (or heat profile) mostly depends on the solder being used. The chip (and other components) datasheet will usually give a maximum temperature and a maximum soldering time.

It may vary a depending of the components, like LED, Crystals, etc...

My experience in microcontroller is that the integrated crystal is the first to go off if it's over heated.


Lead-Free solder (which is the one commonly used in electronics) will met around 240-250°C 
Leaded solder will melt around 200°C.


To do R&amp;D and rework/repair, I usually use special low temperature solder with Bismuth that has a melting point around 130-160°C, this allows to be more "relax" doing the job and worrying less about burning the chip.

Note that as well as the temperature, the humidity is might cause damage while heating. Humidity can slowly get into the chip package and when you heat it up, it might crack the package. If the chip is not out of the package (usually sealed bag with these drying pearls) it is best to first cook the chip/board for a while at 80-90°C to remove the humidity.