Simulation of the Destruction Effects in CMOS- Devices after Impact of Fast Transient Electromagnetic Pulses

Transcription

1 Presented at the COMSOL Conference 2008 Hannover Simulation of the Destruction Effects in CMOS- Devices after Impact of Fast Transient Electromagnetic Pulses M. Rohe, S. Korte and M. Koch Leibniz Universität Hannover In Cooperation with Bundeswehr Research Institute for Protective Technologies and NBC Protection in Munster Cand.-el. Dipl. Ing. Melanie Rohe 1

2 Overview Motivation Threats Disturbing Signals Microscopical Analysis Simulation of Breakdown Simulation of Melting Process Time Behavior of Electric Field and Temperature Summary 2

3 What do you think at this moment, when these error message appears on your screen? What does a flight controller think about?...or a pilot? And Cand.-el. which Dipl.-Ing. consequences Melanie Rohe will it have, if this happens on an intensive care unit? 3

4 Motivation Meaning of electronic systems for the world in the 21st century safety systems medicine economy traffic forces 4

5 Motivation Meaning of electronic systems for the world in the 21st century safety systems medicine economy traffic forces 5

6 Motivation Meaning of electronic systems for the world in the 21st century safety systems medicine economy traffic forces 6

7 Motivation Meaning of electronic systems for the world in the 21st century safety systems medicine economy traffic forces 7

8 Motivation Meaning of electronic systems for the world in the 21st century safety systems medicine economy traffic forces 8

9 NEMP (Nuclear electromagnetic pulse) Threats CIRA (Collapsible IRA; microwave source embossed by explosive material) IRA (Impulse radiating antenna) ESD (Electrostatic discharge) 9

10 E r (t) Disturbing Signals Electromagnetic pulse Voltage on connecting line / (kv/m) u(t) / V ,2 0,4 0,6 0,8 1 x 10-6 t / s Primary coupling path: Connecting lines ,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 x 10-7 t/ s 10

11 % % % 0 E r (t) Electromagnetic pulse Voltage on connecting lines double-exponential form damped harmonic oszillation / (kv/m) r E( t) = E0 Disturbing Signals ( e e β t α t ) u(t) / V t u( t) = U 0 e α sin(2πft) l = 20 cm t 0,2 0,4 0,6 0, ,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 r x 10 t -6 t / s x 10-7 t/ s fwhm Pulse parameter: t r = 7,5 ns t fwhm = 180 ns = 1290 kv/m E max Primary coupling path: Connecting lines Parameter of the coupled-in signal: α = 2, s -1 f 1 = 230 MHz = 821 V U 0 11

12 E (jω) / (V/m) / Hz 10 0 Coupling of electromagnetic pulses 10-2 LEMP NEMP Coupling range 10-4 UWB Source UWB EMP (fast) Nuclear explosion (NEMP) Rise time Pulse duration t r = 100 ps t fwhm = 2.5 ns t r = 1.5 ns t fwhm = 80 ns t r = 1ns 5 ns t fwhm > 100 ns G(jω) / 10-3 m f / Hz l = 20 cm EMP (middle) t r = 5 ns t fwhm = 300 ns EMP (slow) t r > 10 ns t fwhm = 500 ns Lightning (LEMP) t r = 1 µs 2 µs t fwhm 50 µs f 1 f / Hz 12

13 Microscopical Analysis (rear section of an AC-/ACT-Inverter) N-Channel- MOSFET P-Channel- MOSFET Breakthrough Melting Process Diode 13

14 Simulation of Breakthrough (CMOS) 5V 0V 0V E max,si =2, V/m u reg (t) 5V E0V max = 5, V 7 V/m 5V Gate Output S,B D S,B D S,B S, B D S, D B S, B Criterion of breakthrough: E BR,SiO V/m V/m E BR,Si p + n + n-vat p + n + -Polycrystalline Silicon Simulation of the field strength characteristic: E max = 5, V/m < E BR,SiO2 no breakthrough over the whole period of time E max,si = 2, V/m > E BR,Si Drain-Gate-Breakthrough at time t = s but note, that there is no information about the depth faulty simulation results 14

15 Simulation of Melting Process t = 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2, s 5V 5V + u reg (t) T 1 =720K T max = 1092 K Criterion of melting: T Melting,AlSiCu = 933 K 5V Simulation of the temperature characteristic: T 1 = 720 K < T Melting,AlSiCu no destruction T max = 1092 K > T Melting,AlSiCu melting of the conductor line at time t 0, s 15

16 Time behavior of electric field strength and temperature E BR,Si determination of the time of breakthrough is possible the destruction field strength can be determined modifying the input variable until E max = E BR determination of the time of melting process is possible 16

17 Summary Microscopical analysis shows breakthroughs and melting processes both processes can be simulated Information got by the simulations: * time of breakdown * location of the position of the destruction * field strength required for destruction Simulation reproduces the measured results Problems: * only a part of the whole structure could be simulated, because the models are very complex * thin and large structures problems with mesh 17

18 Thank you for your attention! Questions? 18