- Email: [email protected]
An X−Y position sensitive detector
NUCLEAR INSTRUMENTS AND METHODS
54 ( 1967) 323-324; (0 NORTH-HOLLAND PUBLISHING CO.
AN X-Y POSITION' SENSITIVE DETECTOR S. KALISITZER, R. BADER, W. MELZER and W. STUMPF[ Nfax Planck fastifut für Kernphysik, ffeidelherg
Received 21 June 1967 By implantation of boron resp . phosphorus ions into n-type silicon p+-n-n+ junction detectors were produced. The p -" and
nl- resistive layers served to provide X and Y information of the position of incidence of ionizing particles.
X- Y position sensitive detectors (PSD) were produced by implanting ions into wafers of 22 W- cm n-type Sit). Boron was implanted into one side to form a p+-n junction and a homogeneous resistive layer of about 10 kQ as measured between its terminals. This layer is used to get a one dimensional information of the position of incident ionizing particles. Into the other side of the 2 mm thick wafer phosphorus ions were implanted to give a n'-n junction. Again the resistivity of this layer was chosen to be about 10 kQ. This layer can be operated to get a positional information in a direction rectangular to the direction given by the boron layer. The charge dividing process in each resistive layer is similar to that occurring in a one dimensional PSD2). The energy information E can be obtained by summation of the charge pulses either at the X- of the Y-contacts. The charge pulses at the position contacts are proportional to the energy of incident particles. To get an energy independent X-Y position information, the charge pulses of the position
contacts have to be divided by E. By combining the information delivered by the X- and Y-sensitive layers, the position of incidence can be determined. Fig. 1 shows a schematic representation of the device and the electronic equipment used in some measurements demontsrating the X- Y position detection. By using a monoenergetic (x-source the more involved processing techniques described above were avoided. The sensitive area of the detector was 15 mm by 15 mm on both sides of the device . On two sides of each layer heavily implanted regions were added, to which mechanical contacts were applied. The counter was operated with 30 V and at -10° C. Between the source and the detector a plastic sheet with slits of the shape of X and Y was mounted. The results obtained for 24 'Am a-particles penetrating the p}-layer are shown in fig. 2a. The photographs were taken from the oscillographic display of a 1600 channei 'Vtctoreen analyser operated in a two dimensional 1k40 x 40 chan ;~el) mode. The reason far the .k' pattern to appear
c2-19)
X - Y POSITION SENSITIVE DETECTOR
PRE - MAIN AMPLIFIERS
PULSE HEI &hT ANAOSER
Fig. 1 . Schematic representation of the X-Y position sensitive detector and the electronic eq.iipment used . '.'he p' resp . n° la\cr of the ion implanted deteewr was used to obtain X reap . Y information 323
s, KAVaITZER et ail:
Fig. 2. The X-Yïnformation of the device obtained by irradiating through slits of the shape of .X and Y (a) and through 12 equidistant holes (b) with 2ai,g m «_particles . The photographs were taken from the oscillographic display of a pulse height analyser operated in the 44 x 40 channel mode.
broader than Y is' given by the geometrical arrangemeat of source-apertures-detector causing somewhat difterint intensities ofthe a beam at different positions. The small dot in the lower left part of the spectrum is probably due to noise pulses. Another -measurement (fig, ,2b) was carried out with a plastic sheet covered with 12 equidistant holes. From both data we conclude that the resolution in either direction is roughly l mm.
We wish to thank Prof. W. Gentner for his interest in this work. We gratefully acknowledge the cooperation of Dr. K. Bethge and his coworkers of the II. Physikalisches Institut der Universitât Heidelberg . References
r) S. Kalbitzer, R. Bader and H. Herzer, Z. Physik 203 (1967) 117. $) S. Kalbitzer and W. Melzer, to be published.
54 ( 1967) 323-324; (0 NORTH-HOLLAND PUBLISHING CO.
AN X-Y POSITION' SENSITIVE DETECTOR S. KALISITZER, R. BADER, W. MELZER and W. STUMPF[ Nfax Planck fastifut für Kernphysik, ffeidelherg
Received 21 June 1967 By implantation of boron resp . phosphorus ions into n-type silicon p+-n-n+ junction detectors were produced. The p -" and
nl- resistive layers served to provide X and Y information of the position of incidence of ionizing particles.
X- Y position sensitive detectors (PSD) were produced by implanting ions into wafers of 22 W- cm n-type Sit). Boron was implanted into one side to form a p+-n junction and a homogeneous resistive layer of about 10 kQ as measured between its terminals. This layer is used to get a one dimensional information of the position of incident ionizing particles. Into the other side of the 2 mm thick wafer phosphorus ions were implanted to give a n'-n junction. Again the resistivity of this layer was chosen to be about 10 kQ. This layer can be operated to get a positional information in a direction rectangular to the direction given by the boron layer. The charge dividing process in each resistive layer is similar to that occurring in a one dimensional PSD2). The energy information E can be obtained by summation of the charge pulses either at the X- of the Y-contacts. The charge pulses at the position contacts are proportional to the energy of incident particles. To get an energy independent X-Y position information, the charge pulses of the position
contacts have to be divided by E. By combining the information delivered by the X- and Y-sensitive layers, the position of incidence can be determined. Fig. 1 shows a schematic representation of the device and the electronic equipment used in some measurements demontsrating the X- Y position detection. By using a monoenergetic (x-source the more involved processing techniques described above were avoided. The sensitive area of the detector was 15 mm by 15 mm on both sides of the device . On two sides of each layer heavily implanted regions were added, to which mechanical contacts were applied. The counter was operated with 30 V and at -10° C. Between the source and the detector a plastic sheet with slits of the shape of X and Y was mounted. The results obtained for 24 'Am a-particles penetrating the p}-layer are shown in fig. 2a. The photographs were taken from the oscillographic display of a 1600 channei 'Vtctoreen analyser operated in a two dimensional 1k40 x 40 chan ;~el) mode. The reason far the .k' pattern to appear
c2-19)
X - Y POSITION SENSITIVE DETECTOR
PRE - MAIN AMPLIFIERS
PULSE HEI &hT ANAOSER
Fig. 1 . Schematic representation of the X-Y position sensitive detector and the electronic eq.iipment used . '.'he p' resp . n° la\cr of the ion implanted deteewr was used to obtain X reap . Y information 323
s, KAVaITZER et ail:
Fig. 2. The X-Yïnformation of the device obtained by irradiating through slits of the shape of .X and Y (a) and through 12 equidistant holes (b) with 2ai,g m «_particles . The photographs were taken from the oscillographic display of a pulse height analyser operated in the 44 x 40 channel mode.
broader than Y is' given by the geometrical arrangemeat of source-apertures-detector causing somewhat difterint intensities ofthe a beam at different positions. The small dot in the lower left part of the spectrum is probably due to noise pulses. Another -measurement (fig, ,2b) was carried out with a plastic sheet covered with 12 equidistant holes. From both data we conclude that the resolution in either direction is roughly l mm.
We wish to thank Prof. W. Gentner for his interest in this work. We gratefully acknowledge the cooperation of Dr. K. Bethge and his coworkers of the II. Physikalisches Institut der Universitât Heidelberg . References
r) S. Kalbitzer, R. Bader and H. Herzer, Z. Physik 203 (1967) 117. $) S. Kalbitzer and W. Melzer, to be published.