The germanium or silicon is not "vaporized", it is a chip of material that has been cut from a wafer that has been processed using high temperature to diffuse the desired atoms into the wafer to form the transistors.
When it is packaged, the chip is at room temperature, no high pressure involved.
The metal or plastic case is just to protect the chip from atmospheric moisture and other contamination that could damage the transistor.
If you carefully open the case, the transistor will still operate, at least until contaminants cause it to fail.