| 摘要 |
PURPOSE:To provide a method of high measurement accuracy by measuring the temp. of the sample packaged in a shelf and the temp. of the prescribed spacing in the shelf, and determining the wind velocity from the relation between the wind velocity in the shelf and thermal resistance. CONSTITUTION:A semiconductor device for monitoring which permits detection of tip temp. is packaged on a printed board 4 in active state, and a gas for cooling, for example, air is run. In this state, the tip temp. Tj of the semiconductor device and the temp. Ta of the spacing in the shelf by inserting a thermocouple 7 through a small hole are measured. If the power consumption PW of the semiconductor device in this time is determined, the thermal resistance theta of the package of the semiconductor device can be determined by theta=(Tj-Ta)/PW. On the other hand, the relation between the wind velocity (a) of the plate 4 and the thermal resistance theta is beforehand determined, and from the measured value of the thermal resistance theta0, the value of the wind velocity a0 is determined. |
