IEC 60749-39-2021 pdf free download – Semiconductor devices – Mechanical and climatic test methods – Part 39: Measurement of moisture diffusivity and water solubility in organic materials used for semiconductor components.
NOTE Calculating the volume by measuring the linear dimensions is never accurate.The error is smaller whenthe sample is big,One accurate way of determining the volume is to use Archimedes’s principle, which is to way, the volume of a sample with irregular shape can also be determined.
measure the sample weight in air and immersed in a liquid with known density (ethyl alcohol,IPA,etc.). In this 6.2.2 The dry weight of the sample shall be determined, in accordance with lEC 60749-20,firstly by baking the sample for 24 h at 125 +51-0 °C and continuing to bake and weigh thesample every 12 hours until no further weight loss is observed to ensure that the sample(s)are dry. The dry weight is determined when no further weight loss is observed,less than0,002 % difference,after two consecutive measurements with a minimum baking interval of12 h.Within 30 minutes after removal from the oven, weigh the sample(s) using the analyticalbalance equipment described in 4.1 and determine the dry weight in accordance with 6.2.4.
In accordance with IEC 60749-20，small sample(s)(less than 1,5 mm total height), devicesshould be weighed within 30 minutes after removal from oven.
6.2.3 Remove the sample from the bake oven and immediately cool by placing in contactwith the heat sink of 4.5.
lf more than one sample is to be measured,the samples and heat sink should be placed intoa desiccator to limit moisture uptake during the mass ‘measurements.
6.2.4Weigh the sample using the balance described in 4.1 and record the mass asMcomp,dry,1 Read points: At the desired read point; remove the sample(s) from the bake oven. Within30 minutes after removal of the sample(s) from the bake oven, remove the sample(s) from thecontainer and determine their weight using the analytical balance equipment in 4.1. Within30 minutes after weighing the samples, place them in a clean,dry,shallow container so thatthe sample bodies do not touch each other.Return the sample(s) to the bake oven for thedesired time.Continue until the sample(s) have lost all their moisture as determined by thedry weight in 6.2.2.
6.2.5 Placethe sample(s)into a stainless steel holder and transfer to atemperature/humidity chamber stabilized at a pre-set temperature and humidity.
The sample should be transferred into a stainless-steel holder that has been preheated andstabilized to the set chamber temperature.
6.2.6 At accumulative times, remove the sample from the temperature/humidity chamber,cool and measure the sample mass in accordance with 6.2.4.Record the mass as Mcomp,wet,t
6.2.7 Read Points: The x-axis (time) read points，in accordance with IEC 60749-20，are short (24 h or less) because the curve will have a steep initial slope.Later readings can be reach saturation between 0,3 % and 0,4 % when stored at 8o5 ” C/85 % RHLC D esicep Sfal L kept at room ambient between removal from the oven or chamber and weighing and subsequent reinsertion into the oven or chamber.
Ensure that no condensed moisture from the chamber walls comes into contact with a sampleduring removal from the temperature/humidity chamber. If condensed water should contact asample，immediately dry the sample using nitrogen or dry air. The sample should then bereturned to the chamber for re-equilibration and another data point taken at a later time.
The sample weight measurement shall be made within a few minutes after removal of thesample from the temperature/humidity chamber.Time delays longer than 5 minutes afterremoval from the temperature/humidity chamber couldaffect the sample weightmeasurements.IEC 60749-39 pdf download.