in surface packaging of thin resin packages such as surface mount resin molded memory ics or the like , cracks of the package occur frequently at a solder reflow step where thermal impact is applied to the package because the resin has absorbed moisture before packaging . to solve this problem , the devices are sealed in a bag moisture - tight at an assembly step of the resin molded devices where the resin is still dry , and are taken out from the bags immediately before the execution of surface packaging . the devices are packaged in a moisture - proofing bag made of a laminate film , and a desiccant is sealed in the moisture - proofing bag together with the , e . g ., surface mount semiconductor device having a plastic package encapsulating the semiconductor device .