Variations of carrier recombination and trapping parameters due to - PowerPoint PPT Presentation

Variations of carrier recombination and trapping parameters due to anneals in Si irradiated with various particles J.Vaitkus, E.Gaubas, T. Č eponis, A.Mekys, D.Meskauskaite,V.Rumbauskas, V.Vertelis Vilnius University, Institute of Applied Research, Vilnius, Lithuania M.Moll, C.Gallrapp, F.Ravotti CERN Outline (as a new “cheap” Si we still wait from Lancaster U, we concentrate on details of different Si different irradiated, also a series of samples are ready for calibration at CERN).  Carrier recombination and trapping characteristics  Lifetime variations in different type Si under isothermal (80 C) anneals  Lifetime variations Si under isochronal (24) anneals in temperature range of 100-300 C  Recombination and trapping lifetime variations in Si irradiated with various particles  Deep centres in highly irradiated by neutrons Si  Summary

The device for integrated fluence monitoring • The device for the contactless fluence monitoring delivered to CERN, the instruction book given, the seminar for the staff members organized, Vilnius team member is ready to come if necessary. • The calibration procedure has started, and to proton and neutron irradiation the irradiation by pions was added.

. Trapping and recombination lifetime variations dependent on trap concentration, level activation energy and excitation density T N      tr C , V , e , h , Ttr K ; K 1 inst , tr R tr tr   2 ( N n ) C , V , e , h , Ttr 0 0 10 10 1 - E tr = 0.2 eV 1 - E tr = 0.2 eV E tr = 0.3 eV E tr = 0.3 eV 2 - 0.3 2 - 0.3 3 3 6 6 10 10 3 - 0.35 3 - 0.35 4 - 0.4 4 - 0.4 5 - 0.5 5 - 0.5 -1 -1 10 10 5 5 2 2 10 10 2 2  I (a.u.)  I (a.u.) 5 5  I (a.u.)  I (a.u.) 4 4 3 3 3 3 1 1 1 1 10 10 14 cm 14 cm -3 -1 -3 -1 4 4 M tr = 1*10 M tr = 1*10 -2 -2 10 10 14 -2 14 -2 5*10 5*10 2 2 15 -3 15 -3 1*10 1*10 0 0 15 -4 15 -4 10 10 5*10 5*10 16 -5 16 -5 1 1 1*10 1*10 16 -6 16 -6 E r = 0.43 eV, E tr = 0 E r = 0.43 eV, E tr = 0 5*10 5*10 be prilipimo -7 be prilipimo -7 7 7 -3 -3 -1 -1 10 10 10 10 20 20 30 30 40 40 50 50 60 60 20 20 30 30 40 40 50 50 60 60 -1 ) -1 ) -1 ) -1 ) 1/kT (eV 1/kT (eV 1/kT (eV 1/kT (eV a- Simulated trapping coefficient dependence on temperature for trapping level with activation energy of 0.23 eV in Si. b- Variations of recombination and instantaneous trapping lifetimes as a function of reciprocal thermal energy varying activation energy and concentration of trapping centres.

Recombination lifetime as a function of fluence in the as-irradiated Si materials 4 10 Okmetic MCZ<100> 1kOhm·cm 300  m MWR, CIS 8556- 14 wafers 1 - 63 passivated CIS 8556- 14 wafers measured by DG technique 3 10 CIS 8556-01 diodes neutron irradiated 2 10  R (ns) 1 10 0 10 -1 10 12 13 14 15 16 10 10 10 10 10 2 ) Fluence (n/cm

Recombination characteristics of the proton irradiated and isothermally ( T an =80 C) annealed Si 26 GeV protons FZ-n Cz-p As-irradiated As-irradiated Annealed: Annealed: 3 3 10 10 o C 4 min. o C 4 min. 80 80 o C 8 min. 80 o C 8 min. 80 o C 16 min. 80 o C 16 min. 2 80 2 10 10  R (ns)  R (ns) o C 30 min. 80 o C 30 min. 80 1 10 1 10 0 10 0 10 12 13 14 15 16 10 10 10 10 10 12 13 14 15 16 10 10 10 10 10 -2 ) -2 ) Fluence (cm Fluence (cm

Recombination lifetime in Cz and FZ Si samples as a function of pion fluence as-irradiated Cz Si corrected for s Cz Si 2 10 Annealed at T=80 C t exp =4 min Cz Si t exp =4 min corrected for s Cz Si 1 t exp =4+8 min corrected for s Cz Si 10 t exp =4+8+16 min corrected for s Cz Si t exp =4+8+16+32min corrected for s Cz Si  R, eff (  s) t exp =2h+4min corrected for s Cz Si 0 10 t exp =4h+12min corrected for s Cz Si t exp =8h+28min corrected for s Cz Si -1 10 -2 10 11 12 13 14 15 10 10 10 10 10 -2 )  (cm as-irradiated Fz Si 2 10 corrected for s Fz Si Annealed at T=80 C t exp =4 min corrected for s Fz Si t exp =4+8 min corrected for s Fz Si 1 10 t exp =4+8+16 min corrected for s Fz Si  R, eff (  s) t exp =4+8+16+32min corrected for s Fz Si t exp =2h+4min corrected for s Fz Si 0 t exp =4h+12min corrected for s Fz Si 10 t exp =8h+28min corrected for s Fz Si -1 10 -2 10 11 12 13 14 15 10 10 10 10 10 -2 )  (cm

Comparison of characteristics of the pion, neutron and proton irradiated and isothermally ( T an =80 C) annealed Si FZ n-Si (native oxide) 300 MeV pions 2 as -irradiated 10 80 C annealed 510 min. 26 GeV protons (non-corr.  s ) 1 10 as -irradiated 80 C annealed 70 min. 0 reactor neutrons MCz n-Si 10  R (  s) surfaces passivated with therm.SiO as -irradiated -1 10 80 C annealed 1440 min. -2 10 -3 10 -4 10 11 12 13 14 15 16 10 10 10 10 10 10 -2 )  1 MeV n eqv. (cm

Trap spectra in 6.6 MeV electron irradiated Si samples as a function of fluence evaluated by O- I-DLTS - = V 2 +VP V 2 60 (c) 0 = V 3 VO O-I-DLTS signal (arb. units.) E A-V IO 2 ln(  em ´ v th ´ N C ) (a) 58 -1 56 -2 = VO V 2 E A-V - 54 V 2 +VP IO 2 -3 = V 52 3 0.00 50 100 150 200 -1 ) n-Cz 1/kT (eV  =10 16 cm -2 (b) 16 e/cm 2  2 ´ 10 16 e/cm 2  3 ´ 10 -0.02 16 e/cm 2  4 ´ 10 16 e/cm 2  5 ´ 10 -0.04 60 90 120 150 180 210 T (K) The Arrhenius plots obtained for different separated spectral peaks are illustrated in figure (c) for sample irradiated with fluence of Φ =1 × 10 16 e/cm 2 .

DLTS spectra in electron irradiated Si samples after isochronal (24 h) anneals C-DLTS signal (arb. units.) n-Cz 16 e/cm 2  =10 = V 5 as irradiated 2 Annealed VO - 4 o C V 60 (b) V 2 O T an = 80 2 V 3 O ln(  em ´ v th ´ N C ) o C 180 58 = 3 V o C 2 280 VO 56 - V 2 3 54 V 3 O V 2 O VP - 1 V 52 3 50 0 50 100 150 200 250 300 50 100 150 200 250 -1 ) 1/kT (eV T (K) DLTS spectra dependent on annealing temperature recorded on Schottky diodes irradiated with fluence of Φ =10 16 e/cm 2 . b- The Arrhenius plots obtained for different spectral peaks obtained in diodes annealed at 280 ° C.

MW-PC characteristics in electron irradiated Si samples after isochronal (24 h) anneal at T an =280 C varying scan temperature T for transients MW-PC signal (arb. units.) T (K) 16 e/cm 2 , T an =280 o C n-Cz,  =4 ´ 10 280240 200 160 120 1 T=110 K 2 0 10 (a) 10 2 130 K (b) 3 250 K 4 290 K  R ,  tr (  s) -1 10 16 cm -2  =4 ´ 10 1 1 10 o C T an =280 2  R  tr 3 -2 10 4 0 10 40 60 80 100 -3 -1 ) 10 1/kT (eV 0 50 100 150 t (  s) a- The MW-PC transients recorded on the diode sample irradiated with fluence 4 × 10 16 e/cm 2 the carrier recombination ( τ R ) and using different scan temperatures T . b-Variations of trapping ( τ tr ) lifetimes as a function of the reciprocal thermal energy ( kT ) for sample irradiated with fluence 4 × 10 16 e/cm 2 after heat treatment at T a = 280 ° C.

Trapping spectra measured by MW-PC in 6.6 MeV electron irradiated Si samples after isochronal (24 h) anneal at T an =280 C varying scan temperature T of transients Comparison of the simulated (curves) and experimental (symbols) variations of the carrier trapping lifetimes τ tr as a function of reciprocal thermal energy for samples irradiated with fluence 4 ´ 10 16 e/cm 2 and annealed for 24 h at temperatures T an =180 0 C (a) and T an =280 0 C (b). Here, the bold curve represents a sum of emission flows from different trapping levels those form the single thermal emission peaks, shown by thin solid curves. Simulations of the resultant τ tr ( T ) spectrum were performed including temperature dependent changes of the recombination lifetime τ R (T).

Parameters of the carrier emission centres dependent on heat-treatment temperature extracted by O-I-DLTS and MW-PC techniques Heat- treatmen Non-annealed Annealed at 80°C at 180°C at 280°C t Φ=10 16 1 5 1 5 1 5 1 5 e/cm 2 Defect Concentration of trapping centres (10 14 cm -3 ) Method  / V 2 DLTS 0.83 2.2 1.2 2.1 0.7 0.21 - - V  P V 2 O DLTS 0.08 0.083 - 0.12 - - 0.21 0.23 3 MW-PC - - - - - 3.4 - 5 V 3 O DLTS 0.035 - 0.18 - 0.15 - 0.17 0.065 MW-PC - - 0.97 1.8 - - - - = V 3 DLTS - >10 >100 >100 - >100 - MW-PC - - 6 15 - 9 4 3 V 2 = DLTS 11 6.4 14 8.5 - 8.1 1.9 - MW-PC - - 1.4 - 1.2 0.2 0.5 - VO DLTS 3.1 5.6 4.8 7.9 2.7 5 1.4 - IO 2 DLTS - 0.072 0.95 0.19 2.7 0.14  V 3 DLTS - - 0.84 2.2 0.96 0.1 0.96 0.1 A-V DLTS - - >100 - >100 - - -