Title :
Thermosonic gold-ball bond accelerated life test
Author_Institution :
Sandia Nat. Lab., Albuquerque, NM, USA
Abstract :
Accelerated aging tests on gold-ball bonds in hermetic packages have been conducted at 350°C, 300°C, 250°C, and 200°C to determine time to failure, activation energy of failure, and the electrical/mechanical degradation at failure. Four different aluminium/1% silicon metallizations were tested: evaporated metal with P-glass (passivation-glass) contamination, evaporated metal with no P-glass contamination, sputtered metal with P-glass contamination, and sputtered metal with no P-glass contamination. The measured activation energies were from 0.4 to 1.1 eV. Two failure modes were encountered; one was an electrical open with good mechanical strength, and the second was an electrical open that resulted from a premature ball lift caused by voiding under the ball bond. The projected time to failure using an Arrhenius plot indicated that the functional life of gold-ball bonds can exceed 20 yr at ambient temperature if the wire-bonder setup is optimized and the contamination level is low
Keywords :
ageing; aluminium alloys; gold; lead bonding; life testing; reliability; silicon alloys; 20 y; 350 to 200 C; Al-Si metallisations; Arrhenius plot; Au-AlSi; accelerated aging tests; accelerated life test; activation energy of failure; electrical degradation; electrical open with good mechanical strength; failure modes; functional life; hermetic packages; life prediction; mechanical degradation; passivation glass contamination; premature ball lift; reliability; sputtered metal; thermosonic Au ball bond; time to failure; voiding; Accelerated aging; Aluminum; Bonding; Contamination; Degradation; Life estimation; Life testing; Metallization; Packaging; Silicon;
Conference_Titel :
Electronic Components and Technology Conference, 1990. ., 40th
Conference_Location :
Las Vegas, NV
DOI :
10.1109/ECTC.1990.122226
