Abstract
In this paper, we fabricated PRT(platinum resistance thermometers) with the trimming technology using high fine laser system. U. V.(wavelength: 355nm) laser was mainly used for adjusting Pt thin films resistors to 100Ω at 0$^{\circ}C$. Internationally, the accepted A-class tolerance of temperature sensor is ${\pm}$0.06Ω at 0$^{\circ}C$. according to DIN EN 60751. The width of trimmed lines was about 10$\mu\textrm{m}$ and the best trimming conditions of Pt thin films were power : 37mW, frequency : 200Hz and bite size:1.5$\mu\textrm{m}$. And 96 resistors, fabricated by photolithography and etching process, have 79∼90Ω and 91∼102Ω as the proportion of 45.7% and 57.3%, respectively. As result of sitting Pt thin films resistors to the target value(109.73Ω at 25$^{\circ}C$), 82.3% of all resistors had the tolerance within ${\pm}$0.03Ω and the others(17.7%) were within ${\pm}$0.06Ω of A-class tolerance. The PRTs which wore fabricated in this research had excellent characteristics as follows; high accuracy, international standard TCR(temperature coefficient of resistance) value, long-term stability, wide temperature range, good linearity and repeatability, rapid response time, etc.