A polarization maintaining optical device may include a polarization maintaining optical array. A laser beam is applied onto a dicing street of the necessary semiconductor formation region and onto its straight extension in order to remove partial areas of the low dielectric constant filmwiring line stack structure components of the necessary semiconductor formation region and the unnecessary semiconductor formation region so that first groove and the second groove are formed. , a curing agent that is solid at room temperature and has a softening point of not less than 40\xb0 C.