AOS Semiconductor Product Reliability Report AO4915/AO4915L, rev A Plastic Encapsulated Device ALPHA & OMEGA Semiconductor, Inc 495 Mercury Drive Sunnyvale, CA 94085 U.S. Tel: (408) 830-9742 www.aosmd.com Sep 12, 2005 This AOS product reliability report summarizes the qualification result for AO4915. 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 AO4915 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 information Environmental Stress Test Summary and Result Reliability Evaluation Quality Assurance Information I. Product Description: Absolute Maximum Ratings TA=25°C unless otherwise noted Units Parameter Symbol Drain-Source Voltage VDS V Gate-Source Voltage VGS V Continuous Drain Current TA=25°C A Max Q2 ID TA=70°C Pulsed Drain Current B TA=25°C Power A Dissipation Max Q1 TA=70°C Junction and Storage Temperature Range A IDM PD W TJ, TSTG °C Absolute Maximum Ratings TA=25°C unless otherwise noted Parameter Symbol Drain-Source Voltage VDS Continuous Drain Current TA=25°C A Units V ID TA=70°C Pulsed Drain Current Power A Dissipation Max Schottky B TA=25°C TA=70°C Junction and Storage Temperature Range IDM A PD W TJ, TSTG °C Thermal Characteristics : n-channel , p-channel and schottky Parameter Maximum Junctionto-Ambient Maximum Junctionto-Ambient Maximum Junctionto-Lead Maximum Junctionto-Ambient Maximum Junctionto-Ambient Maximum Junctionto-Lead Maximum Junctionto-Ambient Maximum Junctionto-Ambient Maximum Junctionto-Lead Symbol t ≤ 10s SteadyState SteadyState t ≤ 10s SteadyState SteadyState t ≤ 10s SteadyState SteadyState RθJA RθJL RθJA RθJL RθJA RθJL Device Typ Max n-ch 48 62.5 n-ch 74 110 n-ch 35 40 p-ch 48 62.5 p-ch 74 110 p-ch 35 40 schottky 47.5 62.5 schottky 71 110 schottky 32 40 Units °C/W °C/W °C/W II. Package Information: AO4915 Standard sub-micron low voltage P channel process Package Type 8 lead SOIC Lead Frame Copper with Solder Plate Die Attach Silver epoxy Bond wire 2 mils Au wire Mold Material Epoxy resin with silica filler Filler % (Spherical/Flake) 90/10 Flammability Rating UL-94 V-0 Backside Metallization Ti / Ni / Ag Moisture Level Up to Level 1 * Process AO4915 (Green Compound) Standard sub-micron low voltage P channel process 8 lead SOIC Copper with Solder Plate Silver epoxy 2 mils Au wire Epoxy resin with silica filler 100/0 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 AO4915 (Standard) & AO4915L (Green) Test Item Test Condition Time Point Solder Reflow Precondition Normal: 1hr PCT+3 cycle IR reflow@240℃ ℃ (260℃ ℃ for Green) 0hr HTGB Temp = 150 C, Vgs=100% of Vgsmax 168 / 500 hrs 1000 hrs HTRB Temp = 150 C, Vds=80% of Vdsmax Lot Attribution Normal: 81 lots Green: 23 lots Pressure Pot 130 +/- 2 C, 85%, 33.3 psi, Vgs = 80% of Vgs max 121 C, 15+/-1 PSIG, RH=100% Number of Failures 14410 pcs 0 246 pcs 0 (Note B**) (Note A*) 168 / 500 hrs 1000 hrs 100 hrs 77+5 pcs / lot 246 pcs (Note A*) HAST Total Sample size Normal: 52 lots Green: 16 lots 0 77+5 pcs / lot 3740 pcs 0 50+5 pcs / lot 96 hrs (Note B**) Normal: 70 lots Green: 20 lots 4950 pcs 0 50+5 pcs / lot Temperature Cycle -65 to 150 deg C, air to air, 0.5hr per cycle 250 / 500 cycles (Note B**) Normal: 81 lots Green: 23 lots 5720 pcs 0 50+5 pcs / lot (Note B**) DPA Internal Vision Cross-section X-ray CSAM NA 5 5 5 5 5 5 0 NA 5 5 0 Bond Integrity Room Temp 150C bake 150C bake 0hr 250hr 500hr 40 40 40 40 wires 40 wires 40 wires 0 Solderability 230C 5 sec 15 15 leads 0 Note A: The HTGB and HTRB reliability data presents total of available AO4915 and AO4915L burn-in data up to the published date. Note B: The pressure pot, temperature cycle and HAST reliability data for AO4915L comes from the AOS generic green compound package qualification data. IV. Reliability Evaluation FIT rate (per billion): MTTF = 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 (AO4915). 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 MTBF = 10 / FIT = x 10 hrs = years / [2 (164) (168) (258)] = 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: 55 deg C 70 deg C 85 deg C 100 deg C 115 deg C Af 258 87 32 13 5.64 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 10E-5V / K 130 deg C 150 deg C 2.59 1 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