SMT is a more direct production department, applying some manufacturing process technology, but generally a little more physical effort.
PE is more similar to technical support analysis, because it is not a direct production department, but not R & D, so its position is often not very strong in the factory. (In factories, especially large factories, there is a strong supervisor and departmental leadership, there will be less to go a lot of wrong way) but PE is closer to the core technology of the product, as long as you do a good job, and later jumped into the transition for the R & D or something, the salary and SMT is not a concept.
SMT inside the process and equipment engineers or more promising, if the foreign language is better, the process out to foreign companies, wages are also very high.
The SMT process and equipment engineers are still relatively promising.