I was trying to solder some VQFN packaged chips for the first time using a hot air gun, because that's all I have. I set the temperature to rougly < 350°C and startet the process. Sometimes it wouldn't workout perfectly from the beginning on so I had to hold it for a bit longer (up to 30-50 seconds) or make some corrections using a solder iron. A lot of these chips were not working properly. Later on I figured out how to do it faster and manged to get two of them to work.
Now I started to wonder if I really destroyed these chips by overheating them. I really don't think the silicon or any other material was damaged by this. But what about the bond wires? Is it possible that they desoldered/detached?