Semiconductor structures with airgaps andor metal linings and methods of manufacture are provided. The invention also provides a method of making the washer and a coupler device. The shell of the steam cleaner is internally provided with the dust absorbing device with the telescopic dust absorbing head; and the switch controls the dust absorbing head to be telescopic and absorb the dust. A system clock synthesizer calculates differences in value between successively sampled count values from the latch, averages the differences in value to create an average difference value, and normalizes a difference between the average difference value and a target value to create a phase error value.