TY - JOUR
T1 - Cadmium Telluride X-ray pad detectors with different passivation dielectrics
AU - Gädda, A.
AU - Ott, J.
AU - Karadzhinova-Ferrer, A.
AU - Golovleva, M.
AU - Kalliokoski, M.
AU - Winkler, A.
AU - Luukka, P.
AU - Härkönen, J.
PY - 2019/4/21
Y1 - 2019/4/21
N2 - The suitability of two low-temperature dielectric passivation layer processes for the fabrication of Cadmium Telluride (CdTe) X-ray detectors has been investigated. The CdTe crystals with a size of (10×10×1)mm 3 were coated with sputtered aluminum nitride (AlN) or with aluminum oxide (Al 2 O 3 ) grown by the atomic layer deposition (ALD) method. The metallization contacts of the detectors were made by titanium tungsten (TiW) and gold (Au) metal sputtering depositions. The pad detector structures were patterned with proximity-contactless photolithography techniques followed by lift-off patterning of the electrodes. The detector properties were characterized at room temperature by Transient Current Technique (TCT) measurements. The obtained results were compared and verified by numerical TCAD simulations of the detector response. Our results indicate that higher signal charge was collected from samples with Al 2 O 3 . Furthermore, no significant laser light induced signal decay by CdTe material polarization was observed within order of 30 min of continuous illumination.
AB - The suitability of two low-temperature dielectric passivation layer processes for the fabrication of Cadmium Telluride (CdTe) X-ray detectors has been investigated. The CdTe crystals with a size of (10×10×1)mm 3 were coated with sputtered aluminum nitride (AlN) or with aluminum oxide (Al 2 O 3 ) grown by the atomic layer deposition (ALD) method. The metallization contacts of the detectors were made by titanium tungsten (TiW) and gold (Au) metal sputtering depositions. The pad detector structures were patterned with proximity-contactless photolithography techniques followed by lift-off patterning of the electrodes. The detector properties were characterized at room temperature by Transient Current Technique (TCT) measurements. The obtained results were compared and verified by numerical TCAD simulations of the detector response. Our results indicate that higher signal charge was collected from samples with Al 2 O 3 . Furthermore, no significant laser light induced signal decay by CdTe material polarization was observed within order of 30 min of continuous illumination.
KW - Atomic layer deposition (ALD)
KW - Cadmium Telluride (CdTe)
KW - X-ray detector
UR - http://www.scopus.com/inward/record.url?scp=85052741684&partnerID=8YFLogxK
U2 - 10.1016/j.nima.2018.08.063
DO - 10.1016/j.nima.2018.08.063
M3 - Review Article
AN - SCOPUS:85052741684
VL - 924
SP - 33
EP - 37
JO - NUCLEAR INSTRUMENTS AND METHODS IN PHYSICS RESEARCH SECTION A: ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
JF - NUCLEAR INSTRUMENTS AND METHODS IN PHYSICS RESEARCH SECTION A: ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
SN - 0168-9002
ER -