AOS Semiconductor Product Reliability Report AO4423/AO4423L, rev A Plastic Encapsulated Device ALPHA & OMEGA Semiconductor, Inc 495 Mercury Drive Sunnyvale, CA 94085 U.S. Tel: (408) 830-9742 www.aosmd.com Nov 1, 2004 1 This AOS product reliability report summarizes the qualification result for AO4423. 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 AO4423 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. V. Product Description Package and Die information Environmental Stress Test Summary and Result Reliability Evaluation Quality Assurance Information I. Product Description: The AO4423 uses advanced trench technology to provide excellent RDS(ON), and ultra-low low gate charge with a 25V gate rating. This device is suitable for use as a load switch or in PWM applications. It is ESD protected. AO4423L (Green Product) is offered in a lead-free package. Absolute Maximum Ratings TA=25°C unless otherwise noted Parameter Symbol Maximum Units Drain-Source Voltage VDS -30 V Gate-Source Voltage VGS ±25 V TA=25°C Continuous Drain Current G TA=70°C Pulsed Drain Current C TA=25°C B Power Dissipation TA=70°C Junction and Storage Temperature Range Thermal Characteristics Parameter Maximum Junction-toAmbient Maximum Junction-toAmbient Maximum Junction-to-Lead -15 ID -12.1 IDM -80 3.1 PD W 2 TJ, TSTG -55 to 150 Symbol t ≤ 10s SteadyState SteadyState A RθJA RθJL °C Typ Max Units 26 40 °C/W 50 75 °C/W 14 24 °C/W 2 II. Die / Package Information: Process AO4423 AO4423L (Green Compound) Standard sub-micron Standard sub-micron low voltage P channel process low voltage P channel process Package Type Lead Frame Die Attach Bond wire Mold Material Filler % (Spherical/Flake) Flammability Rating Backside Metallization Moisture Level 8 leads SOIC Copper with Solder Plate Ag epoxy 2 mils Au wire Epoxy resin with silica filler 50/50 UL-94 V-0 Ti / N / Ag Up to Level 1 * 8 leads SOIC Copper with Solder Plate Ag epoxy 2 mils Au wire Epoxy resin with silica filler 100/0 UL-94 V-0 Ti / N / Ag Up to Level 1* Note * based on info provided by assembler and mold compound supplier III. Result of Reliability Stress for AO4423 (Standard) & AO4423L (Green) Test Item Test Condition Time Point Lot Attribution Total Sample size Solder Reflow Precondition HTGB Normal: 1hr PCT+3 cycle IR reflow@240 °c (260°c for Green) Temp = 150 C, Vgs=100% of Vgsmax 0hr Normal: 48 lots Green: 16 lots 9405 pcs 168 / 500 hrs Normal: 1 lot 82 pcs 1000 hrs (note A*) 168 / 500 hrs Normal: 1 lot 1000 hrs (note A*) 100 hrs Normal: 30 lots Green: 14 lots HTRB HAST Pressure Pot Temperature Cycle Temp = 150 C, Vds=80% of Vdsmax 130 +/- 2 C, 85%, 33.3 psi, Vgs = 80% of Vgs max 121 C, 15+/-1 PSIG, RH=100% -65 to 150 deg C, air to air, 0.5hr per cycle 96 hrs 250 / 500 cycles (note B**) Normal: 48 lots Green: 16 lots (note B**) Normal: 48 lots Green: 15 lots (note B**) Number of Failures 0 0 77+5 pcs / lot 82 pcs 0 77+5 pcs / lot 2420 pcs 0 50+5 pcs / lot 3520 pcs 0 50+5 pcs / lot 3465 pcs 0 50+5 pcs / lot 3 III. Result of Reliability Stress for AO4423 (Standard) & AO4423L (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 230°C 5 sec 15 15 leads 0 Die shear 150°C 0hr 10 10 0 Note A: The HTGB and HTRB reliability data presents total of available AO4423 and AO4423L burn-in data up to the published date. Note B: The pressure pot, temperature cycle and HAST reliability data for AO4423L comes from the AOS generic green compound package qualification data. IV. Reliability Evaluation FIT rate (per billion): 42.7 MTBF = 2671 years 500 hrs of HTGB, 150 deg C accelerated stress testing is equivalent to 15 years of lifetime at 55 deg C operating conditions (by applying the Arrhenius equation with an activation energy of 0.7eV and 60% of upper confidence level on the failure rate calculation). AOS reliability group also routinely monitors the product reliability up to 1000 hr at and performs the necessary failure analysis on the units failed for reliability test(s). The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in sample size of the selected product (AO4423). Failure Rate Determination is based on JEDEC Standard JESD 85. FIT means one failure per billion hours. Failure Rate = Chi2 x 109 / [2 (N) (H) (Af)] = 1.83 x 109 / [2 (164) (500) (258.24)] = 42.7 MTBF = 109 / FIT = 2.34 x 107hrs =2671 years 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 = 55C) 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 = Boltznan’s constant, 8.617164 X 10 E-5V / K 4 V. Quality Assurance Information Acceptable Quality Level for outgoing inspection: 0.1% for electrical and visual. Guaranteed Outgoing Defect Rate: < 25 ppm Quality Sample Plan: conform to Mil-Std-105D Contacts: Wei Liu, Engineer of Failure Analysis and Reliability [email protected] Jackey Wang, Engineer of Failure Analysis and Reliability [email protected] Fred Chang, Manager of Failure Analysis and Reliability [email protected] Wilson Ma, Senior Director of Quality Assurance [email protected] 5