AOS Semiconductor Product Reliability Report AO3438/AO3438L, rev A Plastic Encapsulated Device ALPHA & OMEGA Semiconductor, Inc 495 Mercury Drive Sunnyvale, CA 94085 U.S. Tel: (408) 830-9742 www.aosmd.com 1 This AOS product reliability report summarizes the qualification result for AO3438. Accelerated environmental tests are performed on a specific sample size, and then followed by electrical test at end point. Review of final electrical test result confirms that AO3438 passes AOS quality and reliability requirements. The released product will be categorized by the process family and be monitored on a quarterly basis for continuously improving the product quality. Table of Contents: I. II. III. IV. Product Description Package and Die information Environmental Stress Test Summary and Result Reliability Evaluation I. Product Description: The AO3438/L uses advanced trench technology to provide excellent RDS(ON), low gate charge and operation with gate voltages as low as 1.8V. This device is suitable for use as a load switch or in PWM applications. AO3438 and AO3438L are electrically identical. -RoHs Compliant -AO3438L is Halogen Free 2 II. Die / Package Information: Process Package Type Lead Frame Die Attach Bond wire Mold Material Flammability Rating Backside Metallization Moisture Level AO3438 Standard sub-micron Low voltage N channel process SOT23 Cu, S/pad, Ag spot Ag epoxy Au 2mils Epoxy resin with silica filler UL-94 V-0 Ti / Ni / Ag Up to Level 1 * AO3438L (Green Compound) Standard sub-micron Low voltage N channel process SOT23 Cu, S/pad, Ag spot Ag epoxy Au 2 mils Epoxy resin with silica filler UL-94 V-0 Ti / Ni / Ag Up to Level 1* Note * based on info provided by assembler and mold compound supplier III. Result of Reliability Stress for AO3438 (Standard) & AO3438L (Green) Test Item Test Condition Time Point Lot Attribution Total Sample size Solder Reflow Precondition Standard: 1hr PCT+3 cycle reflow@260°c Green: 168hr 85°c/85RH +3 cycle reflow@260°c Temp = 150°c , Vgs=100% of Vgsmax - Standard: 19 lots Green: 5 lots 3520 pcs 0 82 pcs 0 HTGB 168hrs 500 hrs 1000 hrs Number of Failures 1 lot 77+5 pcs / lot (Note A*) HTRB HAST Pressure Pot Temperature Cycle Temp = 150°c , Vds=80% of Vdsmax 130 +/- 2°c , 85%RH, 33.3 psi, Vgs = 80% of Vgs max 121°c , 29.7psi, RH=100% -65 to 150°c , air to air, 168hrs 500 hrs 1000 hrs 1 lot 100 hrs (Note A*) Standard: 16 lots Green: 2 lots 96 hrs (note B**) Standard: 18 lots Green: 5 lots 250 / 500 cycles 82 pcs 0 77+5 pcs / lot (note B**) Standard: 19 lots Green: 4 lots (note B**) 990 pcs 0 50+5 pcs / lot 1265 pcs 0 50+5 pcs / lot 1265 pcs 0 50+5 pcs / lot 3 III. Result of Reliability Stress for AO3438 (Standard) & AO3438L (Green) Continues DPA Internal Vision Cross-section X-ray CSAM NA 5 5 5 5 5 5 0 NA 5 5 0 Bond Integrity Room Temp 150°c bake 150°c bake 0hr 250hr 500hr 40 40 40 40 wires 40 wires 40 wires 0 Solderability 245°c 5 sec 15 15 leads 0 Note A: The HTGB and HTRB reliability data presents total of available AO3438 and AO3438L burn-in data up to the published date. Note B: The pressure pot, temperature cycle and HAST reliability data for AO3438 and AO3438L comes from the AOS generic package qualification data. IV. Reliability Evaluation FIT rate (per billion): 43 MTTF = 2639 years The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in sample size of the selected product (AO3438). Failure Rate Determination is based on JEDEC Standard JESD 85. FIT means one failure per billion hours. 2 9 9 Failure Rate = Chi x 10 / [2 (N) (H) (Af)] = 1.83 x 10 9 7 MTTF = 10 / FIT = 2.31 x 10 hrs = 2639years / [2x164x500x258] = 43 Chi² = Chi Squared Distribution, determined by the number of failures and confidence interval N = Total Number of units from HTRB and HTGB tests H = Duration of HTRB/HTGB testing Af = Acceleration Factor from Test to Use Conditions (Ea = 0.7eV and Tuse = 55°C) Acceleration Factor [Af] = Exp [Ea / k (1/Tj u – 1/Tj s)] Acceleration Factor ratio list: Af 55 deg C 70 deg C 85 deg C 100 deg C 115 deg C 130 deg C 150 deg C 258 87 32 13 5.64 2.59 1 Tj s = Stressed junction temperature in degree (Kelvin), K = C+273.16 Tj u =The use junction temperature in degree (Kelvin), K = C+273.16 k = Boltzmann’s constant, 8.617164 X 10-5eV / K 4