TY - JOUR
T1 - Boron-layer silicon photodiodes for high-efficiency low-energy electron detection
AU - Šakić, Agata
AU - Nanver, Lis K.
AU - Scholtes, Tom L.M.
AU - Heerkens, Carel Th H.
AU - Knežević, Tihomir
AU - Veen, Gerard Van
AU - Kooijman, Kees
AU - Vogelsang, Patrick
PY - 2011/11/1
Y1 - 2011/11/1
N2 - Silicon photodiodes for use as low-energy electron detectors have been fabricated using a pure-boron technology to form the p+-anode region. The diode I-V characteristics are ideal and uniform over the wafer with low dark currents in the range of 0.6 pA/mm2. An extremely small thickness of the front-entrance window dead layers was achieved for a 1.8 nm B-layer deposition at 700 °C. All other processing layers on the photosensitive surface were removed using selective wet-etching to the B-layer, a process which is studied here with respect to residues and pitting effects that can result from the etching of Al to the B-layer. For the most optimal photodiode, a high relative electron signal gain is obtained: 60% at 500 eV, and 74% at 1 keV. The degradation of the dark current of B-layer photodiodes is examined for 10-min-long irradiation with 1-25 keV electron energies and stable performance is observed provided that the perimeter isolation-oxide is not exposed.
AB - Silicon photodiodes for use as low-energy electron detectors have been fabricated using a pure-boron technology to form the p+-anode region. The diode I-V characteristics are ideal and uniform over the wafer with low dark currents in the range of 0.6 pA/mm2. An extremely small thickness of the front-entrance window dead layers was achieved for a 1.8 nm B-layer deposition at 700 °C. All other processing layers on the photosensitive surface were removed using selective wet-etching to the B-layer, a process which is studied here with respect to residues and pitting effects that can result from the etching of Al to the B-layer. For the most optimal photodiode, a high relative electron signal gain is obtained: 60% at 500 eV, and 74% at 1 keV. The degradation of the dark current of B-layer photodiodes is examined for 10-min-long irradiation with 1-25 keV electron energies and stable performance is observed provided that the perimeter isolation-oxide is not exposed.
KW - Boron deposition
KW - Dark current degradation
KW - Electron detection
KW - Electron irradiation
KW - Electron signal gain
KW - Low-energy electrons
KW - Responsivity
KW - Silicon photodiodes
KW - Ultrashallow junctions
UR - http://www.scopus.com/inward/record.url?scp=80054011888&partnerID=8YFLogxK
U2 - 10.1016/j.sse.2011.06.042
DO - 10.1016/j.sse.2011.06.042
M3 - Article
AN - SCOPUS:80054011888
VL - 65-66
SP - 38
EP - 44
JO - Solid-state electronics
JF - Solid-state electronics
SN - 0038-1101
IS - 1
ER -