1. UNCLASSIFIED Impact of Complex Material Systems on the Radiation Response of Advanced Semiconductors Robert A. Reed Institute for Space and Defense Electronics School of Engineering Vanderbilt University

2. UNCLASSIFIED Overview Introduction Identifying Key Issues Research Program Background Technical Objectives Approach Expected Research Results Technology Transfer

3. UNCLASSIFIED Introduction Today’s integrated circuits are fabricated using complex material systems Multi-layer, planar copper metal traces Tungsten interconnection High-k dielectrics Goal of this work: Advance the state-of-knowledge pertaining to the impact of complex material systems on the radiation response of sub-100 nm semiconductor structures

4. UNCLASSIFIED Key Issues Two key areas of research: Basic mechanisms for single event effects (SEEs) Increased absorbed dose via dose enhancement (DE)

5. UNCLASSIFIED SEEs: Background Physical mechanisms for SEEs Ionizing radiation-induced energy deposition within the semiconductor, Initial electron-hole pair generation, recombination and thermalization, Carrier transport within the semiconductor, The response of the device and circuit to the motion of the electron-hole pair distribution. The goal of the proposed SEE work is to develop an understanding of the impact that complex material systems have on the first three mechanisms Nuclear Reactions Carrier Generation and motion

6. UNCLASSIFIED Nuclear Reactions:Background Ion-Ion nuclear reactions in non-silicon material near the sensitive volume contribute to the soft error response Warren et al. 2005, Dodd et al., TNS 2007, Reed et al. TNS 2007

7. UNCLASSIFIED Nuclear Reactions Technical Objectives: Measurement of energy deposition from reactions Approach: Device Under Test Charge Sensitive Amplifier Shaping Amplifier Multi-Channel Analyzer COUNTS ENERGY (KeV)

8. UNCLASSIFIED Nuclear Reactions Candidate detectors: Expected Results: Identification of critical materials in complex material systems Provide experimental data for simulation effort define in previous talk Photodiode: - Deposit various materials on diode - NASA MSFC and GSFC SOI PIN Diode: - Various amounts of metals - Université Catholique de Louvain

9. UNCLASSIFIED Carrier Distribution MRED simulation of delta ray production for 100 MeV protons Simulation of delta ray production using MC code from SOREQ Technical Objectives: Experimental study of carrier generation and comparison to theories Review carrier motion theories Background:

10. UNCLASSIFIED Carrier Generation Approach: Build stacked array of detectors VU space awarded on DARPA 3D SOI run Measure response Compute energy deposition spectra (MRED and SOREQ) Identify shortcoming of carrier generation theories Review ultrafast nonlinear-optical techniques to study carrier relaxation processes (NRL) Expected Results: Identify shortcoming of carrier generation theories Array of SOI collection volumes

11. UNCLASSIFIED Free Carrier Motion Approach: Review current carrier motion theories Expected Results: Identify shortcoming of carrier motion theories

12. UNCLASSIFIED Key Issues Two key areas of research: Basic mechanisms for single event effects (SEEs) Increased absorbed dose via dose enhancement (DE)

13. UNCLASSIFIED Dose Enhancement: Background D. E. Beutler, et al. IEEE Trans. Nucl. Sci., 1987.

14. UNCLASSIFIED Dose Enhancement: Background D. E. Beutler, et al. IEEE Trans. Nucl. Sci., 1987.

15. UNCLASSIFIED Dose Enhancement Technical Objectives: Develop and validate simulation methodology for dose enhancement effect Approach: Determine simulation methodology for dose enhance effects using MRED Perform dose enhancement simulations and compare to existing experimental data Research to extend the dose enhancement simulations to highly Expected Results Simulation tool to study DE Better understanding of the implications of high-Z materials near active devices for advance semiconductors

16. UNCLASSIFIED Summary of Research Goal: Advance the state-of-knowledge pertaining to the impact of complex material systems on the radiation response of sub-100 nm semiconductor structures

17. UNCLASSIFIED Technology Transfer ISDE Engineering Collaborative R&D, e.g. NRL/Vanderbilt NASA MSFC/Vanderbilt CREME-MC Site DoD vendor relationships NASA Center collaborative R&D Through students