EN 60749-24 EUROPEAN STANDARD NORME EUROPEENNE EUROPAISCHENORM April 2004 ICS 31.080 English version Semiconductordevices- Mechanical and climatic test methods Part 24:Acceleratedmoistureresistance Unbiased HAST (IEC60749-24:2004) Dispositifsasemiconducteurs Halbleiterbauelemente Methodesd'essaismecaniques Mechanische undklimatische etclimatiques Prufverfahren Partie24:RésistanceaIhumidité Teil24:BeschleunigteVerfahrenfur accélérée- Feuchtebestandigkeit HAsTsanspolarisation Hochbeschleunigte Wirkung (HAsT) (CEI60749-24:2004) ohneelektrische Beanspruchung (IEC 60749-24:2004) This European Standard was approved by CENELEC on 2004-04-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. CENELEC EuropeanCommitteeforElectrotechnical Standardization ComiteEuropeendeNormalisationElectrotechnique EuropaischesKomiteefurElektrotechnische Normung Central Secretariat:rue de Stassart 35,B-1050Brussels @ 2004 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60749-24:2004 E EN60749-24:2004 Foreword The text of document 47/1736/FDIS, future edition 1 of IEC 60749-24, prepared by IEC TC 47, Semiconductor devices, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60749-24 on 2004-04-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2005-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2007-04-01 AnnexZAhas beenadded byCENELEC. Endorsement notice The text of the International StandardIEC 60749-24:2004 was approved by CENELEC as a European Standard without any modification. EN60749-24:2004 SEMICONDUCTORDEVICES MECHANICALAND CLIMATICTESTMETHODS- Part 24:Accelerated moisture resistance-UnbiasedHAsT 1 Scopeandobject The unbiased highly accelerated stress testing (HAsT) is performed for the purpose of evaluating the reliability of non-hermetically packaged solid-state devices in humid environments. It is a highly accelerated test which employs temperature and humidity under non-condensing conditionsto acceleratethe penetration of moisture throughtheexternal protective materia metallicconductorswhichpassthroughit.Biasisnotappliedinthistesttoensurethatthe failure mechanisms potentially overshadowed by bias can be uncovered (e.g. galvanic corrosion). This test is used to identify failure mechanisms internal to the package and is destructive NOTE This test is a complete rewrite of the test contained in Clause 4C of Chapter 3 of IEC 60749 (1996) (without bias voltage). 2 Normativereferences The following referenced documents are indispensable for the application of this document. Fordated references,only the edition cited applies.For undated references, the latest edition of the referenced document (including any amendments)applies. IEC60749-33,Semiconductordevices-Mechanicaland climatictestmethods-Part33: Acceleratedmoistureresistance-unbiasedautoclave IEC6o749-5,Semiconductordevices-Mechanicalandclimatictestmethods-Part 5: Steady-statetemperaturehumiditybias lifetest 3 Test apparatus humidity under pressure duringramp-up to, and ramp-downfrom, the specifi