METHOD OF MEASURING THERMAL RESISTANCE BETWEEN A HOUSING OF A SEMICONDUCTOR DEVICE AND A COOLING RADIATOR Russian patent published in 2019 - IPC G01R31/26 G01N25/18 G01N27/18 

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment, namely to nondestructive testing, and can be used for measurement of thermal parameters of semiconductor devices after fabrication and mounting on cooling radiator. Disclosed is a method of measuring thermal resistance between a housing of a semiconductor device and a cooling radiator, which consists in fixing a housing of a controlled semiconductor device on a cooling radiator through a layer of heat-conducting paste. Cooling radiator is placed in heated liquid, temperature of which is not more than 75 % of maximum heating temperature of semiconductor device, wherein housing of semiconductor device is located above level of heated liquid. Measuring n values of voltages of the thermoelectric EMF between the housing of the semiconductor device and the cooling radiator, amplifying them, performing analogue-to-digital conversion, storing and determining n temperature values of the housing of the semiconductor device using the formula: where E_EEMF – measured thermoEMF at the end of i time interval, T_cr is temperature of cooling radiator placed in heated liquid, α – Seebeck coefficient, i – current index, varies from 0 to n, i and n – natural row of numbers, and then average value of thermal resistance by formula: , where C is heat capacity of semiconductor device housing, t₀ is the semiconductor device housing heating process start time, t_i=(Δt⋅i) are time intervals during heating of semiconductor device housing, Δt is value of time interval, T₀ – temperature of housing of semiconductor device before measurement, T_SDi – temperature of the housing of the semiconductor device at the end i of the time interval.

EFFECT: high information value of the obtained measurement data, since the method enables to measure thermal resistance between the housing of any semiconductor device and the cooling radiator after installing the semiconductor device on the cooling radiator, this provides information on the presence and quality of heat-conducting paste application between the semiconductor device and the cooling radiator without removal of the cooling radiator before the semiconductor device is put into operation.

1 cl, 1 dwg