PARTICULATE SUBSTANCE DETECTION SENSOR

PROBLEM TO BE SOLVED: To provide an electric resistance type particulate substance detection sensor used for PM detection in exhaust gas of an internal combustion engine capable of preventing measurement errors due to coarse PM particles and condensed water, suppressing decrease in detection sensitivity, detecting target floating PM with high accuracy and promptly detecting a failure of DPF.SOLUTION: A sensor element part 1 of a PM sensor S attached on an exhaust pipe EX of an engine E/G includes a chamber 21 composed of a concave part provided on a particulate substance detection surface 20 of an insulation substrate 10, a pair of measurement electrodes 24, 25 formed on the bottom surface of the chamber 21 and a particulate substance detection part 2 composed of an insulation protective layer 22 facing the electrodes leaving an interval with them. A lot of fine through-holes 23 through which only particulate materials to be detected can pass are formed on the insulation protective layer 22.