TY - JOUR
T1 - High-efficiency silicon photodiode detector for sub-keV electron microscopy
AU - Sakic, Agata
AU - van Veen, Gerard
AU - Kooijman, Kees
AU - Vogelsang, Patrick
AU - Scholtes, Tom L.M.
AU - de Boer, Wiebe B.
AU - Derakhshandeh, Jaber
AU - Wien, Wim H.A.
AU - Milosavljevic, Silvana
AU - Nanver, Lis K.
PY - 2012/8/15
Y1 - 2012/8/15
N2 - A silicon photodiode detector is presented for use in scanning electron microscopy (SEM). Enhanced imaging capabilities are achieved for sub-keV electron energy values by employing a pure boron (PureB) layer photodiode technology to deposit nanometer-thin photosensitive anodes. As a result, imaging using backscattered electrons is demonstrated for 50-eV electron landing energy values. The detector is built up of several closely packed photodiodes, and to obtain high scanning speed, each photodiode is engineered with low series resistance and low capacitance values. The low capacitance (< 3 pF/mm 2) is facilitated by thick, almost intrinsically-doped epitaxial layers grown to achieve the necessarily wide depletion regions. For the low series resistance, diode metallization has been patterned into a conductive grid directly on top of the nanometer-thin PureB-layer front-entrance window. Finally, a through-wafer aperture in the middle of the detector is micromachined for flexible positioning in the SEM system.
AB - A silicon photodiode detector is presented for use in scanning electron microscopy (SEM). Enhanced imaging capabilities are achieved for sub-keV electron energy values by employing a pure boron (PureB) layer photodiode technology to deposit nanometer-thin photosensitive anodes. As a result, imaging using backscattered electrons is demonstrated for 50-eV electron landing energy values. The detector is built up of several closely packed photodiodes, and to obtain high scanning speed, each photodiode is engineered with low series resistance and low capacitance values. The low capacitance (< 3 pF/mm 2) is facilitated by thick, almost intrinsically-doped epitaxial layers grown to achieve the necessarily wide depletion regions. For the low series resistance, diode metallization has been patterned into a conductive grid directly on top of the nanometer-thin PureB-layer front-entrance window. Finally, a through-wafer aperture in the middle of the detector is micromachined for flexible positioning in the SEM system.
KW - Backscattered electrons (BSEs)
KW - Boron layer
KW - Electron detector
KW - Low-energy electrons
KW - Silicon epitaxy
KW - Silicon photodiode
UR - http://www.scopus.com/inward/record.url?scp=84866739115&partnerID=8YFLogxK
U2 - 10.1109/TED.2012.2207960
DO - 10.1109/TED.2012.2207960
M3 - Article
AN - SCOPUS:84866739115
SN - 0018-9383
VL - 59
SP - 2707
EP - 2714
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
IS - 10
M1 - 6261542
ER -