Thickness and refractive index measurement of a silicon wafer based on an optical comb.
We have proposed and demonstrated a novel method that can determine both the geometrical thickness and refractive index of a silicon wafer at the same time using an optical comb. The geometrical thickness and refractive index of a silicon wafer was determined from the optical thickness using phase information obtained in the spectral domain. In a feasibility test, the geometrical thickness and refractive index of a wafer were measured to be 334.85 microm and 3.50, respectively. The measurement uncertainty for the geometrical thickness was evaluated as 0.95 microm (k = 1) using a preliminary setup.
Jin
Jonghan
J
Center for Length and Time, Division of Physical Metrology, Korea Research Institute of Standards and Science (KRISS), Science Town, Daejeon, 305-340, Republic of Korea. jonghan@kriss.re.kr
Kim
Jae Wan
JW
Kang
Chu-Shik
CS
Kim
Jong-Ahn
JA
Eom
Tae Bong
TB
D007259:Infrared Rays; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods; D007834:Lasers; D008962:Models, Theoretical; D055096:Optical Devices; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D012825:Silicon / Q000737:chemistry*; D013053:Spectrophotometry / Q000295:instrumentation* / Q000379:methods
D012825:Silicon