A surface treatment method for solder joint employs alkali buffer solution dipping the solder joint and the alkali buffer solution reacts with the solder joint thus yielding a passive layer. Any client that supports these extensions can utilize these features. The device may receive a request to provide a first copy of the content to a requesting device. One-bit program data and information of whether the program unit stores program data or not can be read based on two program signals generated according to the electric resistances of the two program cells.