An optical sensing enhancing material comprising: a medium, the medium comprising a plurality of aggregated nanoparticles comprising fractals; and a microcavity, wherein the medium is located in a vicinity of the microcavity. The base station receives an uplink signal transmitted by a first subscriber station. The steps of the method comprises: first, determining where the user data transmitted; then, using one of two error correction circuits which have different error correction capability to encode or decode the user data. Organic groups with terminal carboxylic acid functionality can be converted to an acyl chloride and further reacted with an amine to form an amide or with a diamine to form an amide with terminal amine. Also, a WRITE-AFTER-WRITE operation similarly is accomplished by interposing a PRECHARGE operation between subsequent WRITE operations. The method includes providing a film including a first material and a second material and removing the second material contained in the film by dry etching.