Methods are given for making scale inhibitors, that were previously incompatible with fluids containing fluoride ion, compatible with fluids containing fluoride ion. The process comprises an activating step in which said surface is contacted with an activating solution, a sensitising step in which said surface is contacted with a sensitising solution, and a subsequent silvering step in which said surface is contacted with a silvering solution comprising a source of silver to form the silver coating. The memory circuit region includes a memory device region in communication with the memory control device region. The handle includes a first portion with a color chosen from the first group of colors. In order to suppress an influence on a lower wiring which has been manufactured, heating is carried out for a short time of approximately 5 to 10 minutes by using the hot plate. The engaging portion is located in the first groove.