anna macchiolo* * max-planck-institut f ü r physik

RD50 Recent Results

Development of radiation hard sensors for SLHC

Anna Macchiolo*Anna Macchiolo***Max-Planck-Institut fMax-Planck-Institut füür Physikr Physik

on behalf of the RD50 Collaboration

The RD50 Collaboration: scope and methods Defect characterization Results on irradiated detectors Planar pixel productions 3D sensor developments

OUTLINEOUTLINE

http://www.cern.ch/rd50http://www.cern.ch/rd50

RD50

8 North-American institutesCanada (Montreal), USA (BNL, Fermilab, New Mexico, Purdue,

Rochester, Santa Cruz, Syracuse)

1 Middle East instituteIsrael (Tel Aviv)

247 Members from 47 Institutes

Detailed member list: http://cern.ch/rd50

Development of Radiation Hard Semiconductor Devices for High Luminosity Colliders

38 European institutes Belarus (Minsk), Belgium (Louvain), Czech Republic (Prague (3x)), Finland (Helsinki, Lappeenranta), Germany (Dortmund,

Erfurt, Freiburg, Hamburg, Karlsruhe, Munich), Italy (Bari, Florence, Padova, Perugia, Pisa, Trento), Lithuania (Vilnius),

Netherlands (NIKHEF), Norway (Oslo (2x)), Poland (Warsaw(2x)), Romania (Bucharest (2x)), Russia (Moscow,

St.Petersburg), Slovenia (Ljubljana), Spain (Barcelona, Valencia), Switzerland (CERN, PSI), Ukraine (Kiev),

United Kingdom (Glasgow, Lancaster, Liverpool)

RD50: Nov.2001 collaboration formed ; June 2002 approved by CERN

A. Macchiolo – Max-Planck-Institut für Physik VERTEX 2009 Workshop- Putten (NL) 14th September 2009 -3-

RD50

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n-in-n (FZ), 285m, 600V, 23 GeV p p-in-n (FZ), 300m, 500V, 23GeV pp-in-n (FZ), 300m, 500V, neutrons

p-in-n-FZ (500V)n-in-n FZ (600V)

M.Moll - 08/2008

References:

[1] p/n-FZ, 300m, (-30oC, 25ns), strip [Casse 2008][2] n/n-FZ, 285m, (-10oC, 40ns), pixel [Rohe et al. 2005]

FZ Silicon Strip and Pixel Sensors

strip sensorspixel sensors

Motivation:

Signal degradation for LHC Silicon Sensors

Strip sensors: max. cumulated fluence for LHC

Pixel sensors: max. cumulated fluence for LHC


RD50

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p-in-n-FZ (500V)n-in-n FZ (600V)

M.Moll - 08/2008

References:

[1] p/n-FZ, 300m, (-30oC, 25ns), strip [Casse 2008][2] n/n-FZ, 285m, (-10oC, 40ns), pixel [Rohe et al. 2005]

FZ Silicon Strip and Pixel Sensors

strip sensorspixel sensors

Motivation:

Signal degradation for LHC Silicon Sensors

Strip sensors: max. cumulated fluence for LHC and SLHC

Pixel sensors: max. cumulated fluence for LHC and SLHC


RD50 Material Engineering -- Defect Engineering of Silicon

Understanding radiation damage• Macroscopic effects and Microscopic defects• Simulation of defect properties & kinetics• Irradiation with different particles & energies

Oxygen rich Silicon• DOFZ, Cz, MCZ, EPI

Oxygen dimer & hydrogen enriched Silicon Influence of processing technology

Material Engineering-New Materials (work concluded) Silicon Carbide (SiC), Gallium Nitride (GaN)

Device Engineering (New Detector Designs) p-type silicon detectors (n-in-p) thin detectors 3D detectors Simulation of highly irradiated detectors Semi 3D detectors and Stripixels Cost effective detectors

Development of test equipment and measurement recommendations

RD50 approaches to develop radiation harder tracking detectors

Radiation Damage to Sensors:

Bulk damage due to NIEL Change of effective doping concentration Increase of leakage current Increase of charge carrier trapping

Surface damage due to IEL (accumulation of positive charge in oxide

& interface charges)


RD50 Silicon Material under Investigation

DOFZ silicon - Enriched with oxygen on wafer level, inhomogeneous distribution of oxygen CZ/MCZ silicon - high Oi (oxygen) and O2i (oxygen dimer) concentration (homogeneous)

- formation of shallow Thermal Donors possible Epi silicon - high Oi , O2i content due to out-diffusion from the CZ substrate (inhomogeneous)

- thin layers: high doping possible (low starting resistivity) Epi-Do silicon - as EPI, however additional Oi diffused reaching homogeneous Oi content

standardfor

particledetectors

used for LHC Pixel

detectors

“new”silicon

material

Material Thicknessm]

Symbol (cm)

[Oi] (cm-3)

Standard FZ (n- and p-type) 50,100,150300

FZ 1–3010 3 < 51016

Diffusion oxygenated FZ (n- and p-type) 300 DOFZ 1–710 3 ~ 1–21017

Magnetic Czochralski Si, Okmetic, Finland (n- and p-type)

100, 300 MCz ~ 110 3 ~ 51017

Czochralski Si, Sumitomo, Japan (n-type)

300 Cz ~ 110 3 ~ 8-91017

Epitaxial layers on Cz-substrates, ITME, Poland (n- and p-type)

25, 50, 75,100,150

EPI n: 50 – 500 p: 50-1000

< 11017

Diffusion oxyg. Epitaxial layers on CZ 75 EPI–DO 50 – 100 ~ 61017


RD50 Defect Characterization - WODEAN

WODEAN project (initiated in 2006, 10 RD50 institutes, guided by G.Lindstroem, Hamburg)

Aim: Identify defects responsible for Trapping, Leakage Current, Change of Neff

Method: Defect Analysis on identical samples performed with the various tools available inside the RD50 network (DLTS, TSC, TCT, etc.)

~ 240 samples irradiated with protons and neutrons

Example: identification of defects responsible for long term / reverse annealing

Cluster related defects H(116K), H(140K) and H(152K) (not present after -irradiation) observed in neutron irradiated n-type Si diodes during 80oC annealing

Concentrations are increasing with annealing time contribute to long term/ reverse annealing

Neff can be calculated from measured defect concentrations with TSC including BD and E(30K) defects

Comparison with Neff from CV-measurements shows a very good compatibility


RD50

I.Pintilie, NSS, 21 October 2008, Dresden

Summary – defects with strong impact on the device properties at operating temperature

Point defects

EiBD = Ec – 0.225 eV

nBD =2.310-14 cm2

EiI = Ec – 0.545 eV

nI =2.310-14 cm2

pI =2.310-14 cm2

Cluster related centers

Ei116K = Ev + 0.33eV

p116K =410-14 cm2

Ei140K = Ev + 0.36eV

p140K =2.510-15 cm2

Ei152K = Ev + 0.42eV

p152K =2.310-14 cm2

Ei30K = Ec - 0.1eV

n30K =2.310-14 cm2

V2 -/0

VO -/0 P 0/+

H152K 0/-

H140K 0/-

H116K 0/-CiOi

+/0

BD 0/++

Ip 0/-

E30K 0/+

B 0/-

0 charged at RT

+/- charged at RT

Point defects extended defects

Reverse annealing

(neg. charge)

leakage current+ neg. charge

(current after irradiation)

positive charge (higher introduction after

proton irradiation than after neutron irradiation)

positive charge (high concentration in oxygen

rich material)


RD50 Silicon materials for Tracking Sensors Signal comparison for various Silicon sensors Note: Measured partly

under different conditions! Lines to guide the eye

(no modeling)!

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SiC

p-in-n (EPI), 150 m [7,8]p-in-n (EPI), 75m [6]

75m n-EPI

150m n-EPI

n-in-p (FZ), 300m, 500V, 23GeV p [1]n-in-p (FZ), 300m, 500V, neutrons [1]n-in-p (FZ), 300m, 500V, 26MeV p [1]n-in-p (FZ), 300m, 800V, 23GeV p [1]n-in-p (FZ), 300m, 800V, neutrons [1]n-in-p (FZ), 300m, 800V, 26MeV p [1]

n-in-p-Fz (500V)

n-in-p-Fz (800V)

p-in-n (FZ), 300m, 500V, 23GeV p [1]p-in-n (FZ), 300m, 500V, neutrons [1]n-FZ(500V)

M.Moll - 08/2008

References:

[1] p/n-FZ, 300m, (-30oC, 25ns), strip [Casse 2008][2] p-FZ,300m, (-40oC, 25ns), strip [Mandic 2008][3] n-SiC, 55m, (2s), pad [Moscatelli 2006][4] pCVD Diamond, scaled to 500m, 23 GeV p, strip [Adam et al. 2006, RD42] Note: Fluenze normalized with damage factor for Silicon (0.62)[5] 3D, double sided, 250m columns, 300m substrate [Pennicard 2007][6] n-EPI,75m, (-30oC, 25ns), pad [Kramberger 2006][7] n-EPI,150m, (-30oC, 25ns), pad [Kramberger 2006][8] n-EPI,150m, (-30oC, 25ns), strip [Messineo 2007]

Silicon Sensors

Other materials

n-in-p microstrip p-type FZ detectors (Micron, 280 or 300m thick, 80m pitch) Detectors read-out with 40MHz (SCT 128A)


RD50 Silicon materials for Tracking Sensors Signal comparison for various Silicon sensors Note: Measured partly

under different conditions! Lines to guide the eye

(no modeling)!

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SiC

p-in-n (EPI), 150 m [7,8]p-in-n (EPI), 75m [6]

75m n-EPI

150m n-EPI

n-in-p (FZ), 300m, 500V, 23GeV p [1]n-in-p (FZ), 300m, 500V, neutrons [1]n-in-p (FZ), 300m, 500V, 26MeV p [1]n-in-p (FZ), 300m, 800V, 23GeV p [1]n-in-p (FZ), 300m, 800V, neutrons [1]n-in-p (FZ), 300m, 800V, 26MeV p [1]

n-in-p-Fz (500V)

n-in-p-Fz (800V)

p-in-n (FZ), 300m, 500V, 23GeV p [1]p-in-n (FZ), 300m, 500V, neutrons [1]n-FZ(500V)

M.Moll - 08/2008

References:

[1] p/n-FZ, 300m, (-30oC, 25ns), strip [Casse 2008][2] p-FZ,300m, (-40oC, 25ns), strip [Mandic 2008][3] n-SiC, 55m, (2s), pad [Moscatelli 2006][4] pCVD Diamond, scaled to 500m, 23 GeV p, strip [Adam et al. 2006, RD42] Note: Fluenze normalized with damage factor for Silicon (0.62)[5] 3D, double sided, 250m columns, 300m substrate [Pennicard 2007][6] n-EPI,75m, (-30oC, 25ns), pad [Kramberger 2006][7] n-EPI,150m, (-30oC, 25ns), pad [Kramberger 2006][8] n-EPI,150m, (-30oC, 25ns), strip [Messineo 2007]

Silicon Sensors

Other materials

highest fluence for strip detectors in LHC: The used p-in-n technology is sufficient

n-in-p technology should be sufficient for Super-LHC at radii presently (LHC) occupied by strip sensors

LHC SLHC

RD50 Charge Multiplication –FZ Strip Sensors

• CCE increases at SLHC fluences over the expectations• CCE>100% charge multiplication! • Most results showing an anomalous high charge collection efficiency

have been obtained until now with Micron FZ n-on-p strip detectors

• Read-out with SCT128A, 25 ns shaping• Possible dependence on manufacturer process details

investigated with measurements on sensors from a second producer (Hamamatsu Photonics) within the “ATLAS Upgrade Strip Sensor Collaboration”

• Studies concentrated on fluences relevant to pixels (ATLAS Insertable B-layer and SLHC)

• Preliminary results show a compatible CCE behaviour

[ M. Mikuž, Hiroshima Symposium 2009 ]

RD50 Charge Multiplication –Epi Diodes

• Epi diodes, 75 and 150 m thick• Measured trapping probability found to be proportional

to fluence and consistent with values extracted in FZ• Multiplication effect more evident for 75 m diodes• Smaller penetration depth (670 nm laser) stronger

charge multiplication

n-type,


RD50 Mixed irradiations: 23 GeV protons+neutronsMicron diodes irradiated with protons first and then with 2e14 n cm-2 (control samples p-only, open marker)

• FZ-p,n: increase of Vfd proportional to Feq• MCz-n: decrease of Vfd , due to different signs of gc,n and gc,p• MCz-p at larger fluences the increase of Vfd is not proportional to the added fluence –as if material becomes more “n-like” with fluence – same as observed in annealing plots

80min@60oC 80min@60oC

neqncpeqpcC ggN ,,,, gc can be + or -

always +

nnppeq

[ G. Kramberger, 13th RD50 Workshop,Nov. 2008, http://dx.doi.org/10.1016/j.nima.2009.08.030 ]


RD50 Mixed Irradiations (Neutrons+Protons)

Both FZ and MCz show “predicted” behaviour with mixed irradiation

FZ doses add• |Neff| increases

MCz doses compensate• |Neff| decreases, proton damage

compensate part of the neutron damage

1x1015 neq cm-2

[T.Affolder 13th RD50 Workshop, Nov.2008]

Mixed irradiation performed with: 5x1014 p (1 MeV equivalent fluence) 5x1014 n (1 MeV equivalent fluence)

More charge collected at 500 V after additional irradiation!

RD50 Planar pixel productions

MPP-HLL thin pixel production (75 and 150 m) on n- and p-type FZ silicon using a wafer bonding technique that allows variable thicknesses down to 50 m

Pre-irradiation characterization of the p-type wafers shows high yield and good breakdown performances

RD50 Planar Pixel project : production of pixels at CiS (CMS and ATLAS geometries) on FZ and MCz silicon with R&D focus on: - direct comparison of n-in-n and n-in-p performances - slim edges (needed for inner pixel layers in ATLAS) - Pixel isolation methods (moderated, uniform p-spray)

n-in-n wafer design

[M. Beimforde 14th RD50 Workshop, June 2009]

p-type pixels


RD50 “3D” electrodes: - narrow columns along detector thickness,

- diameter: 10m, distance: 50 - 100m Lateral depletion: - decoupling of detector thickness and charge collection distance - lower depletion voltage needed

- fast signal - radiation hard

Development of 3D detectors

Fabrication of 3D detectors challenging: modified design under investigation within RD50

Columnar electrodes of both doping types are etched into the detector from both wafer sides

Columns are not etched through the entire detector: no need for wafer bonding technology but column overlap defines the performance.

n+ columns

p+columnsp-type substrate

metal

oxide

3D-DDTC

Two manufacturers: CNM (Barcelona): 14 wafers (p- and n-type) completed Oct. 2008 FBK (Trento): 3 3D-DDTC batches fabricated with different overlaps


RD50 3D-DTC sensors –Test-beam data

[M.Koehler 14th RD50 Workshop, June.2009]

front column

back column

Overall efficiency: 97.3% Overall efficiency: 98.6%

No clustering strips with highest and 2nd highest signal joined into clusters

2D efficiency at 40 V for Q>2fC

Device from FBK: p-type strip sensor, 50 m column overlap Test-beam at CERN: 225 GeV/c muons and APV25 analogue readout (40 MHz)

Strip structure is clearly visible only when clustering is not applied.


RD50 Test equipment: ALIBAVA ALIBAVA – A LIverpool BArcelona VAlencia collaboration System supported by RD50: Will enable more RD50 groups to investigate

strip sensors with ‘LHC-like’ electronics

[R.Marco-Hernández, 13th RD50 Workshop, Nov.2008]

Plug and Play System: Software part (PC) and hardware part connected by USB.

Hardware part: a dual board based system connected by flat cable.

Mother board intended:• To process the analogue data that comes from

the readout chips.• To process the trigger input signal in case of

radioactive source setup or to generate a trigger signal if a laser setup is used.

• To control the hardware part.• To communicate with a PC via USB.

Daughter board • It contains two Beetle readout chips • It has fan-ins and detector support to interface

the sensors. Software part:

It controls the whole system (configuration, calibration and acquisition).

It generates an output file for further data processing.


RD50 RD50 achievements & links to LHC Experiments

Some important contributions of RD50 towards the SLHC detectors: p-type silicon (brought forward by RD50 community) is now considered to be

the base line option for the ATLAS Strip Tracker upgrade

n- MCZ (introduced by RD50 community) has improved performance in mixed fields due to compensation of neutron and proton damage: MCZ is under investigation in ATLAS, CMS and LHCb

RD50 results on very highly irradiated silicon strip sensors have shown that planar pixel sensors are a promising option also for the upgrade of the Experiments.

Charge multiplication effect observed for heavily irradiated sensors (diodes and strips). A dedicated R&D effort will be launched in RD50 to understand the underlying multiplication mechanism and optimize the CCE performances.


RD50

Spares


RD50

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FZ <111>FZ <111>DOFZ <111> (72 h 11500C)DOFZ <111> (72 h 11500C)MCZ <100>MCZ <100> CZ <100> (TD killed) CZ <100> (TD killed)

FZ, DOFZ, Cz and MCz Silicon

24 GeV/c proton irradiation (n-type silicon)

Strong differences in Vdep

Standard FZ silicon Oxygenated FZ (DOFZ) CZ silicon and MCZ silicon

Strong differences in internalelectric field shape (type inversion, double junction,…)

Different impact on pad and strip detector operation!

e.g.: a lower Vdep or |Neff| does not necessarily correspond to a higher CCE for strip detectors (see later)!

Common to all materials (after hadron irradiation): reverse current increase increase of trapping (electrons and holes) within ~ 20%


RD50 n-in-p microstrip detectors

n-in-p microstrip p-type FZ detectors (Micron, 280 or 300m thick, 80m pitch, 18m implant ) Detectors read-out with 40MHz (SCT 128A)

CCE: ~7300e (~30%) after ~ 11016cm-2 800V

n-in-p sensors are strongly considered for ATLAS upgrade (previously p-in-n used)

Sign

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[G.Casse, RD50 Workshop, June 2008]

Fluence(1014 n eq/cm2 )0 100 200 300 400 500

time at 80oC[min]

0 500 1000 1500 2000 2500time [days at 20oC]

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6.8 x 1014cm-2 (proton - 800V)6.8 x 1014cm-2 (proton - 800V)

2.2 x 1015cm-2 (proton - 500 V)2.2 x 1015cm-2 (proton - 500 V)

4.7 x 1015cm-2 (proton - 700 V)4.7 x 1015cm-2 (proton - 700 V)

1.6 x 1015cm-2 (neutron - 600V)1.6 x 1015cm-2 (neutron - 600V)

M.MollM.Moll

[Data: G.Casse et al., NIMA 568 (2006) 46 and RD50 Workshops][Data: G.Casse et al., NIMA 568 (2006) 46 and RD50 Workshops]

no reverse annealing in CCE measurementsfor neutron and proton irradiated detectors

RD50 Charge Multiplication –FZ strip sensors

CCE increases at SLHC fluences over the expectations at high fluences CCE>100% charge multiplication! Micron n-on-p FZ strip detectors Read-out with SCT128A, 25 ns shaping Multiplication effect more relevant for thin (140 m) FZ structures at higher fluences: after heavy irradiation it is

possible to recover the full ionized charge For pixel layers this has the potential benefit of reducing the radiation length of the detector and yield a safer S/N

[I. Mandic et al., NIM A603 (2009) 263 ] [G. Casse, 14th RD50 Workshop, June 2009]

300 m


RD501. CNM Barcelona ( 2 wafers fabricated in Nov. 2007) Double side processing with holes not all the way through n-type bulk bump bond 1 wafer to Medipix2 chips Further production (n and p-type)

Processing of Double-Column 3D detectors

10m

p+n-

TEOS

Poly

Junction

2. FBK (IRST-Trento) very similar design to CNM 2 batches produced (n-type and p-type )

First tests on irradiated devices performed ( CNM devices, strip sensors, 90Sr , Beetle chip, 5x1015neq/cm2 with reactor neutrons) : 12800 electrons


RD50 2008 test beam with 3D sensors Two microstrip 3D DDTC detectors tested in testbeam (CMS/RD50)

• One produced by CNM (Barcelona), studied by Glasgow• One produced by FBK-IRST (Trento), studied by Freiburg

[M.Koehler 13th RD50 Workshop, Nov.2008]


RD50 3D-DTC sensors –Test-beam data

anna macchiolo* * max-planck-institut f ü r physik

Documents

cumulated fluence

slhc pixel sensors

lhc rd50motivation

investigation dofz silicon

finland n

rd50 collaboration

standard fz n

diffusion oxygenated