1. CONFIDENTIAL WP2 Review Meeting Milan, October 05, 2011 MODERN ENIAC WP2 Meeting (WP2-T2.1) WP2 and Tasks review Milano Agrate, 2011 Oct. 05 Meeting hosted by Micron

2. CONFIDENTIAL 11 WP2: Relationship among work packages WP2 Review Meeting Milan, October 05, 2011

3. CONFIDENTIAL 2 T2.1 Task Task T2.1: PV-aware process simulation Process simulation tools will be extended to include the impact of variations in TCAD simulations especially in etching and deposition processes; an interface to commercial process and device simulation programs will be developed. Process simulations for the extraction of behavioral models will be performed. In addition it is intended to build up an interface between the process simulation environment and the semiconductor FAB to obtain equipment parameters which affect variability. Partners: ST-I, AMS, TUW In the analysis and modelling of PV ST-I wants to link process information out of the silicon manufacturing facility into TCAD environment in order to take into account inevitable process variations and doping fluctuations with the objectives to create a behavioural model of the process to be simulated and to perform statistical process analysis and process optimization to improve parametric yield. AMS and TUW will focus on TCAD process simulation to reflect major sources for PV in 0.35um, 0.18um and 0.13um CMOS and HV technologies; main inline/equipment parameters will be taken into account. TCAD based statements about pros and cons of emerging device options will be given concerning variability. The methodology will be compared to the one used in task 2.2. WP2 Review Meeting Milan, October 05, 2011

4. CONFIDENTIAL 3 Process simulation: T2.1 Deliverables RefDeliverable/ ContributorsDue date D2.1.1 First process simulation including treatment of PV for Discrete Power Device, HV-CMOS, SiC, GaN/AlGaN technologies, interfaced to commercial TCAD tools (ST-I, AMS, TUW) M15 DONE D2.1.2Enhanced process simulation including treatment of PV for Discrete Power Device, HV-CMOS, SiC, GaN/AlGaN technologies, interfaced to commercial TCAD tools (ST-I, AMS, TUW) M27 DONE Task Leader: valeria.cinnera@st.com Partners: ST-I, AMS, TUW Task 2.1 goal is to perform process simulation including treatment of PV. Application for discrete power devices, SiC, AlGaN/GaN (ST-I) and HV-CMOS technologies (AMS) WP2 Review Meeting Milan, October 05, 2011

5. CONFIDENTIAL 4 Activity done so far: –Interface between commercial process simulator and fab equipments: a web – based tool has been realized. The tool accepts in input the product code used in manufacturing and produces in output the process parameters that can be passed to the TCAD software tools (Silvaco or Synopsys syntax) (Implementation activity is included in WP5) –Process simulator setup & calibration –Process simulation with Synopsys platform has been performed. –Screening parameters: first device simulations have been executed in order to select the process parameters that mainly affect the electrical behavior of the device: –Design of Experiment has been arranged to build structures with a systematic variation of the selected process parameters. The activity done on a Silicon Power MOS (D2.1.1) has been extended to compound materials (SiC and AlGaN/GaN devices) (D2.1.2) –PCM extraction: polynomials function of process parameters have been extracted (T2.2) –PCM validation: As a check for the robustness of the PCM, a new set of simulation data, choosing a random combination of input parameters, have been generated and compared with the prediction given by the PCM (T2.2) Interactions –T2.1 DOE results  T2.2 for device simulation and PCM extraction. T2.1 Review Summary (ST-I) WP2 Review Meeting Milan, October 05, 2011

6. CONFIDENTIAL 5 Activity done so far, with highlights on technical results, and dissemination -HV-CMOS technologies (AMS, TUW): Statistical fab data analysis (FEOL, BEOL): 0.35µm HV-CMOS Tech.  done HV devices for DOE: NMOSI20T and PMOS20T Process simulator setup & calibration  done Critical PV selection: 6 ~ 8 variables (substrate resistivity, implant dose, CD & overlay, GOX thickness, …)  done PMOS20T process simulations with 7 PV variables  done (see Back-up slides) 286 (W/L=10/0.6, 10/10) structures from process simulations go to Minimos-NT for device simulation. Device simulations for statistical spice modeling: done (PMOS20T) Script development for electrical parameter extraction  inline measurement D2.1.2 deliverable: Done –An interface between commercial process simulator and Minimos-NT (a two-dimensional device simulator from TUW) –Complete set of NMOS20T and PMOS20T process and device simulations  done –Script update for electrical parameter extraction –NMOS20T and PMOS20T sensitivity analysis with 7~8 process variations: done Issues Interaction need: –T2.1 results (HV-CMOS)  T2.3 for Spice Monte-Carlo Model (D2.3.3) T2.1 Review Summary (AMS, TUW) WP2 Review Meeting Milan, October 05, 2011

7. CONFIDENTIAL 6 T2.1 Back-up slides for ST-I WP2 Review Meeting Milan, October 05, 2011

8. CONFIDENTIAL 7 ST-I WP2 Activity High Level factory Process recipes Specific process conditions Mask Layout Process flow Virtual device TCAD Experiments Process Compact model derived from TCAD PCM FAB1 FAB2 Technology transferred to FAB2 using PCM WP2 Review Meeting Milan, October 05, 2011

9. CONFIDENTIAL 8 WEB-Based Interface: High-level factory WP2 Review Meeting Milan, October 05, 2011

10. CONFIDENTIAL 9 T2.1 9 Process compact modeling approach incorporates statistical design of experiment methods within the calibrated TCAD environment allowing to capture relationships between process variations and device performance through a set of analytic functions (Response Surface Method). The flow of PCM extraction from TCAD simulation consists of the following steps: - Definition of a calibrated TCAD flow (process and device); - Analysis of process parameter sensitivity (parameter screening); - Simulations of process splits and electrical variables extraction (design of experiment); - PCM generation. Input process parameters Output device characteristics Process Compact Model Predicted device response New process conditions WP2 Review Meeting Milan, October 05, 2011

11. CONFIDENTIAL 10 Application to Power-Mos cell (D2.1.1) Parameter screening to identify the process parameters that have an important impact on target electrical parameters. Parameterized simulation setup (DOE) generating several simulation runs. Device simulations of breakdown and I-V characteristic for each experiment. D OE EHD5 SEMICELL SENTAURUS WORKBENCH PCM STUDIO PCM Applied methodology flow. Synopsys platform: Sentaurus and PCM Studio Simulation of Power-Mos semi cell with the nominal values of the process input parameters WP2 Review Meeting Milan, October 05, 2011

12. CONFIDENTIAL 11 Process variability 11 VariableDescription epithickThickness of the epitaxial layer epiconc Doping concentration of the epitaxial layer gateoxThickness of the gate oxide bmaskCD of POLY gate mask pmaskCD of JFET mask Input process parameters that have influence on the device behavior. Output electrical parameters: RDSon and BV A large number of process variables requires a very high computational cost. Selecting only those process parameters showing the greatest impact on electrical performances. Sensitivity index for process parameter variation WP2 Review Meeting Milan, October 05, 2011

13. CONFIDENTIAL 12 Design of experiments 12 The DOE depends on the degree of the polynomial required for a good data fit. The output electrical parameter is a non-linear function of the input process parameters, modeled by a second order polynomial. To fit a second-order model, a DOE with at least three levels is required: 81 experiments are generated. For each structure, device simulations are performed to extract Ron and BV. WP2 Review Meeting Milan, October 05, 2011

14. CONFIDENTIAL 13 Application to 4H-SiC JBS diode (D2.1.2) 13 Process StepValue Epi Thickness6 µm Epi Doping1e16 atm/cm3 Pwell mask8 µm PreImplant Oxide Thickness 0.06 µm Error Dose Factor1 (nominal Value) Activation percentage35% Schottky Barrier1.14 eV Resistance Anode0.45e-3 Ω*µm Resistance Schottky1e-7 Ω*µm Resistance Cathode1.1e-3 Ω*µm Forward and reverse characteristics comparison between measure and simulation. Calibration of TCAD simulations WP2 Review Meeting Milan, October 05, 2011

15. CONFIDENTIAL 14 Process variability and DOE setup 14 VariableDescriptionNominalMinMaxUnit Sp Space among p-wells 87.68.4µm EpiTEpitaxy Thickness65.76.3µm EpiDEpitaxy Doping1e169e151.1e16 Atm/cm 3 OxTPre-implant oxide Thickness0.060.0540.066µm errDDose Error10.91.1- AttDoping Activation0.350.10.6% BarrierSchottky Barrier1.141.0831.197eV RcCathode Resistance1.1e-39.9e-41.21e-3Ω Input process parameters that have influence on the device behavior: -FW6 (anode voltage @6A) -FW80 (anode voltage @80A) -BV (breakdown Voltage) -LK600 (leakage current @600V) Parameters screening DOE setup in SWB WP2 Review Meeting Milan, October 05, 2011

16. CONFIDENTIAL 15 Application to AlGaN/GaN HEMTs (D2.1.2) 15 VariableDescriptionNominalMinMaxUnits thAlGaNThickness of the first AlGaN layer252030[nm] GateFootWidth of the gate foot0.50.40.6[µm] GatePlateWidth of the gate plate1.31.21.4[µm] LdgDrain-Gate distance2.52.03.0[µm] LsgSource-Gate distance2.01.52.5[µm] HgateHeight of the gate foot0.080.060.1[µm] GateRecErosion of the AlGaN layer under the gate contact000.02[µm] MolFracMolar fraction of the first AlGaN layer0.260.240.27-- Schematic cross-section of the AlGaN/GaN HEMT under examination Input process parameters that have influence on the device behavior: - Id_MAX (maximum drain current value at Vg=2V) - Vth (threshold voltage) - gm (maximum of transconductance for a given Id– Vg) WP2 Review Meeting Milan, October 05, 2011

17. CONFIDENTIAL 16 Process variability and DOE setup 16 VariableId_MAXVthgm thAlGaN121.3%32.9%76.0% GateFoot0.50%0.69%1.0% GatePlat e 0.33%0.32%1.8% Ldg13.2%0.56%13.6% Lsg16.2%1.0%20.0% Hgate0.08%0.05%2.54% GateRec0.99%87.5%86.5% MolFrac47.4%12.6%32.1% Experiments generated by DoE Sensitivity analysis WP2 Review Meeting Milan, October 05, 2011

18. CONFIDENTIAL 17 Conclusions In D2.1.2 the methodology used to increase TCAD simulation efficiency, by deriving Process Compact Models from systematic well-calibrated simulations, is described. In order to demonstrate the general concepts of how to use the PCM approach, a 4H- SiC JBS diode and an AlGaN/GaN HEMT device have been investigated. The Synopsys platform (Sentaurus and PCM Studio) has been used. First the standard cell of the device under examination has been simulated with the nominal values of the process input parameters. Second the process parameters that have an important impact on target electrical parameters have been identified performing a parameter screening. Then, a parameterized simulation setup has been arranged. To complete the analysis, device simulations have been performed, for each experiment. Moreover post-processing scripts need to be introduced to automatically extract the list of electrical outputs. In this way the RSM model of device characteristics as function of process parameters will be generated by using PCM Studio. Details on this work has been included on D2.2.4. WP2 Review Meeting Milan, October 05, 2011

19. CONFIDENTIAL 18 T2.1 Back-up slides for AMS and TUW WP2 Review Meeting Milan, October 05, 2011

20. CONFIDENTIAL 19 Process Variation Input Parameters (HV-PMOS) SX182022 DN_DOSE4.05E+0124.10E+0124.15E+012 DPOverlay-0.100.1 SNOverlay-0.100.1 PADOX_VthM0.110.0520 Vt_2p7e122.65E+0122.70E+0122.75E+012 TOXTH-202 - 143 (7 PV for HV-PMOS) and 272 (8 PV for HV-NMOS) Full Process and Device Simulations WP2 Review Meeting Milan, October 05, 2011

21. CONFIDENTIAL 20 Process Variation Variation Setup (RSM) WP2 Review Meeting Milan, October 05, 2011

22. CONFIDENTIAL 21 Process Variation TCAD Flow Parameters Sentaurus Work Bench Minimos Parameter Extraction Correlation Interface between commercial Synopsys Process Simulator and Minimos Device Simulator WP2 Review Meeting Milan, October 05, 2011

23. CONFIDENTIAL 22 Process Variation Minimos Device Simulation Linked to commercial Synopsys Process Tools Input from.grd and.dat output of Sentaurus Device Geometry output of Minimos to.grd and.dat Characteristics to.crv Parameter Extraction Inhouse Measurement Methods at AMS extract BSIM Parameters from Simulation Ron, Vth, Idsat, Sleak, Gamma, Leff WP2 Review Meeting Milan, October 05, 2011

24. CONFIDENTIAL 23 Process Variation Parameter Extraction Original Matlab Methods at AMS Rewritten to extract Parameters from Minimos In Python with SciPy and Numpy Nearly identical Syntax as in Matlab WP2 Review Meeting Milan, October 05, 2011

25. CONFIDENTIAL 24 Process Variation Vth Extraction WP2 Review Meeting Milan, October 05, 2011

26. CONFIDENTIAL 25 Process Variation Extracted Data WP2 Review Meeting Milan, October 05, 2011

27. CONFIDENTIAL 26 Process Variation Output Parameters (SNOverlay) WP2 Review Meeting Milan, October 05, 2011

28. CONFIDENTIAL 27 Status of PV-aware Process & Device Simulations Status TypeParametersProcessDeviceParameters HV-PMOS(20/0.6)finished HV-PMOS(20/10)finished HV-NMOS(20/0.7)finished HV-NMOS(20/10)finished Electrical parameter extraction (for Monte Carlo spice model) : done (Vth_lin, Vth_sat, Idlin, Idsat, Ron, Sleak, Gamma, Leff, …)  D2.3.3 *Remarks: HV-PMOS = PMOS20T, HV-NMOS=NMOSI20T WP2 Review Meeting Milan, October 05, 2011

29. CONFIDENTIAL 28 Quadratic fitting from the simulation results - H35 technology (0.35 µm HV-CMOS process) - PMOS20T: 143 structures (7 PV) - NMOSI20T: 272 structures (8 PV)  TCAD Process & device simulations (sprocess & Minimos-NT)  Quadratic fitting (all PV versus electrical data)  Random 10000 PV-set generation by considering inline PV distributions  Electrical parameter calculation from the quadratic formula  Data analysis WP2 Review Meeting Milan, October 05, 2011

30. CONFIDENTIAL 29 PMOS20T(20/0.6): Ron and Ron-fit WP2 Review Meeting Milan, October 05, 2011

31. CONFIDENTIAL 30 PMOS20T(20/0.6): Vthlin and Vthlin-fit WP2 Review Meeting Milan, October 05, 2011

32. CONFIDENTIAL 31 PMOS20T(20/0.6): Ron and Vthlin correlation WP2 Review Meeting Milan, October 05, 2011

33. CONFIDENTIAL 32 PMOS20T(20/0.6): 7 PV distributions (10000 random values) WP2 Review Meeting Milan, October 05, 2011

34. CONFIDENTIAL 33 PMOS20T(20/0.6): Ron and Vthlin distribution WP2 Review Meeting Milan, October 05, 2011

35. CONFIDENTIAL 34 PMOS20T(20/0.6) & NMOSI20T(20/0.7): Ron versus Vtlin WP2 Review Meeting Milan, October 05, 2011

36. CONFIDENTIAL 35 Conclusions Statistical fab data analysis (FEOL, BEOL) for 0.35µm HV-CMOS Techhnology was done for PV TCAD simulations. TCAD environment construction: - Process simulator setup & calibration - Critical 7~8 PV selection - Interface development between commercial process simulator and Minimos-NT (a two- dimensional device simulator from TUW) - Script development for electrical parameter extraction TCAD simulations: - A set of NMOS20T and PMOS20T process and device simulations - NMOS20T and PMOS20T sensitivity analysis - Quadratic curve fitting of simulation results, Random PV generation - PV-aware statistical electrical parameters T2.1 results (HV-CMOS)  T2.3 for Spice Monte-Carlo Model (D2.3.3) WP2 Review Meeting Milan, October 05, 2011