Thin diamond film development

Thin diamond film development
M. Nicola Mazziotta
INFN-Bari
PS 136 – Regione Puglia
•
Sviluppo di un rivelatore a film di diamante per radiazione ultravioletta
– Deposizione dei film di diamante poli-/nano-cristallino con la tecnica microwave
plasma enhanced chemical vapour deposition (MWPECVD)
– Sintesi di film PCD (polycrystalline diamond) basata sulla plasma laser deposition
(PLD)
– Caratterizzazione dei film (interferometria pirometrica in situ, SEM, XRD, RAMAN)
– Assemblaggio, caratterizzazione elettrica, elettronica e acquisizione sensori
•
Coordinatore: Paolo Spinelli
– UR1: Dipartimento Interuniversitario di Fisica-Università di Bari “Aldo Moro”
(Paolo Spinelli)
– UR2: Dipartimento Interuniversitario di Fisica-Politecnico di Bari (Nicola Giglietto)
– UR3: CNR-Istituto di Metodologie Inorganiche e dei Plasmi – Bari (Grazia Cicala)
– UR4: Dipartimento di Chimica- Università di Bari “Aldo Moro” (Savino Longo)
– ALTA SpA (Pisa)
– Planetek srl (Bari)
– Aurelia Microelettronica (Viareggio)
•
•
•
Durata: 49 mesi dal 12/2006
Costo totale: 1.961.200€
Cofinanziamento Regione Puglia: 1.339.200€
PS 136 - M. Nicola Mazziotta
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Reattore a plasma
Miscela gassosa con una bassa concentrazione (5%) di CH4 in H2 .
PS 136 - M. Nicola Mazziotta
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Sample
Substrate
(500µm
thick)
Sample-ID
Total film
thickness
(µm)
CH4/H2
(%)
Power (W)
Press.
(mbar)
Avg.
surface
temp. (°C)
Growth
rate
(µm/h)
R (%)*
Grain
size**
(µm)
Roughness
***
(µm)
p-Si
Diam66_1
15.92
1.5
1800
73.5
902
0.337
76.32
1-10
4
i-Si
Diam66_3
15.92
1.5
1800
73.5
902
0.337
77,84
1-6.5
3-4
i-Si
S(6)
57.18
5
3000
200
850
2.18
95,73
5-20
5
p-Si
S(8)
58.87
5
3000
200
850
2.62
97,76
5-20
5-11
* Raman quality factor:
R = Isp3 / (Iphotoluminescence + Isp3 +  Ino_diamond)*100
Diam66_1 on p-Si
Diam66_3 on i-Si
10
8
** Scanning Electron Microscopy, SEM
*** Optical Microscope
6
4
12
S6 on i-Si
S8 on p-Si
a.u.)
2
1200
1400
1600
-1
Raman shift (cm )
1800
3
10
0
Intensity (x10
Intensity (x10 3 a.u.)
12
8
6
4
2
0
1200
PS 136 - M. Nicola Mazziotta
1400
1600
1800
-1
Raman shift (cm )
4
Assemblaggio sensore e caratterizzazione
1 cm
Photolithographic mask
Cr/Au contacts 20/200nm
dark current (nA)
500X
DARK BOX
E (kV/cm)
2
1,5
1
0,5
0
0
2
4
6
8
10
Diam66_1 20m Gap
S(6) 30m Gap
Diam66_3 20m Gap
S(8) 30m Gap
PS 136 - M. Nicola Mazziotta
Thermal annealing at
700°C (1h) in CH4
atmosphere,
followed by 400°C
(1h) in air is very
effective in reducing
dark currents.
5
Optical Characterization Setup
oscilloscope
sensor
Vbias
Xe flash lamp
2000
S(6) Gap 30 m @ 18KV/cm
Vrms=1.56mV
1500
Count
optical
filters
ENC=3600
1000
500
PS 136 - M. Nicola Mazziotta
0
-8
-6
-4
-2
0
2
noise (mV)
4
6
6
S(6) GAP 30m @ 18kV/cm Efield
10000
Straight linear trend
 (nm)
-1
1 x 10
Vout (mV)
1000
1 x 10-2
nm
100
10
Threshold @ 5noise=mV
-3
1 x 10
1
ENC=3560e
1E+5
1E+7
1E+9
Number of incident photons
1 x 10-4
S(6)
S(8)
Diam66_3
Diam66_1
1 x 10-5
150 200 250 300 350 400 450 500 550
Diam66_1 and Diam66_3: C=W= 20 μm
S6 and S8: : C=W= 20 μm
UV/VIS about 102-103
Vout vs Vbias
3000
2500
Vout (mV)
Collected electrons/
Number of incident photons
Results
30 m Gap
2E+8 incident
photons on S(6)
@nm
2000
1500
1000
50 m Gap
500
0
0
10 20 30 40 50 60 70 80
Vbias (V)
PS 136 - M. Nicola Mazziotta
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Diamond films photo-emissivity
PS 136 - M. Nicola Mazziotta
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PHODAC
• PHOtocathodes based on Diamond
Amorphous and Crystalline (PHODAC)
– Realizzazione di fotocatodi a film di diamante per
la rivelazione di radiazione Cherenkov nell’UV
• Collabarozioni:
– Istituto di Metodologie Inorganiche e dei Plasmi
IMIP-CNR Sezione di Bari
– Laboratoire d’Ingénierie des Materiaux et des
Hautes Pressions (LIMHP) del CNRS-UPR –
Université Paris
PS 136 - M. Nicola Mazziotta
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Risultati misure di QE
A.S. Tremsin and O.H.W. Siegmund
Proceedings SPIE, vol. 4139, San Diego,
California (2000)
OUS-14
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Reference
• “Thermoluminescent Response of Thin (< 2 μm) Polycrystalline
Diamond Films Grown by Pulsed and Continuous Microwave
Plasmas”, Diamond and Related Materials 19 470 (2010)
• “Study of polycrystalline diamond deposition by continuous and
pulsed discharges”, Surface & Coatings Technology 204 1884 (2010)
• “Characterization of poly-crystalline diamond films grown by
Microwave Plasma Enhanced Chemical Vapor Deposition
(MWPECVD) for UV radiation detection”, Nuclear Instruments and
Methods in Physics Research A, 617 405 (2010)
• “Mechanical Properties of MWPECVD Diamond Coatings on Si
Substrate via Nanoindentation”, Diamond and Related Materials 20
(2011) 221
• “A comparative study on comb electrodes devices made of
MWPECVD diamond films grown on p-doped and intrinsic silicon
substrate”, Diamond and Related Materials 20 (2011) 1005
• “Effect of Properties of MWPECVD Polycrystalline Diamond Films on
Photoemissive Response”, Diamond and Related Materials 20
(2011) 1199
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