AOS Semiconductor Product Reliability Report AOT404/AOT404L, rev A Plastic Encapsulated Device ALPHA & OMEGA Semiconductor, Inc 495 Mercury Drive Sunnyvale, CA 94085 U.S. Tel: (408) 830-9742 www.aosmd.com Mar 7, 2005 1 This AOS product reliability report summarizes the qualification result for AOT404. 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 AOT4 04 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 AOT404 uses advanced trench technology and design to provide excellent R DS (ON) with low gate charge. This device is suitable for use in high voltage synchronous rectification, load switching and general purpose applications. AOT404L (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 105 V Gate-Source Voltage VGS ±25 V TA=25°C Continuous Drain G Current TA=100°C Pulsed Drain Current Avalanche Current C C TA=25°C B Power Dissipation Junction and Storage Temperature Range 40 ID IDM 100 IAR 20 Maximum Junction-to-Case A 100 PD TA=100°C Thermal Characteristics Parameter Maximum Junction-toAmbient A 28 W 50 TJ , TSTG SteadyState SteadyState -55 to175 °C Symbol Typ Max Units RθJA 50 60 °C/W RθJL 1 1.5 °C/W 2 II. Die / Package Information: Process Package Type Lead Frame Die Attach Bond wire Mold Material Filler % (Spherical/Flake) Flammability Rating Backside Metallization Moisture Level AOT404 AOT404L (Green Compound) Standard sub-micron Standard sub-micron low voltage N channel process low voltage N channel process 3 leads TO220 3 leads TO220 Copper with Ni pad Copper with Ni pad Soft solder Soft solder Al wire, 5&15 mils Al wire, 5&15 mils Epoxy resin with silica filler Epoxy resin with silica filler 50/50 100/0 UL-94 V-0 UL-94 V-0 Ti / Ni / Ag Ti / Ni / Ag Up to Level 1 * Up to Level 1* Note * based on info provided by assembler and mold compound supplier III. Result of Reliability Stress for AOT404 (Standard) & AOT404L (Green) Test Item Test Condition Time Point Solder Reflow Precondition HTGB Normal: 1hr PCT+3 cycle IR reflow@240 °c (260° c for Green) Temp = 150 C, Vgs=100% of Vgsmax HTRB HAST Pressure Pot Temperature Cycle Temp = 150 C, Vds=80% of Vdsmax Lot Attribution Total Sample size 0hr Normal: 9 lots 1210pcs 168 / 500 hrs Normal: 2 lots 164pcs 1000 hrs (Note A*) 168 / 500 hrs Normal: 2 lots 1000 hrs (Note A*) 130 +/- 2 C, 85%, 33.3 psi, Vgs = 80% of Vgs max 100 hrs 121 C, 15+/-1 PSIG, RH=100% 96 hrs -65 to 150 deg C, air to air, 0.5hr per cycle 250 / 500 cycles Number of Failures 0 0 77+5 pcs / lot 164pcs 0 77+5 pcs / lot Normal: 8 lots 440pcs 0 Normal: 9 lots 50+5 pcs / lot 495pcs 0 Normal: 5 lots 50+5 pcs / lot 275pcs 0 50+5 pcs / lot 3 III. Result of Reliability Stress for AOT404 (Standard) & AOT404L (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 AOT404 and AOT404L burn-in data up to the published date. IV. Reliability Evaluation FIT rate (per billion): 14.4 MTBF = 7927 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 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 (AOT404). Failure Rate Determination is based on JEDEC Standard JESD 85. FIT means one failure per billion hours. 2 9 / [2 (N) (H) (Af)] = 1.83 x 10 / [2 (164) (500) (258.24)+ 2 (164) (1000) (258.24)] = 14.4 7 Failure Rate = Chi x 10 9 9 MTBF = 10 / FIT =6.9x 10 hrs = 7927years 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] Fred Chang, Manager of Failure Analysis and Reliability [email protected] Wilson Ma, Senior Director of Quality Assurance [email protected] 5