Semiconductor radiation detector, positron emission tomography apparatus, semiconductor radiation detection apparatus, detector unit and nuclear medicine diagnostic apparatus

Abstract

Each semiconductor radiation detector used for a nuclear medicine diagnostic apparatus (PET apparatus) is constructed with an anode electrode A facing a cathode electrode C sandwiching a CdTe semiconductor member S which generates charge through interaction with γ-rays. Then, a thickness t of the semiconductor member S sandwiched between these mutually facing anode electrode A and cathode electrode C is set to 0.2 to 2 mm. Furthermore, the devices are mounted (laid out) on substrates in such a way that the distance (distance of conductor) between the semiconductor radiation detector and an analog ASIC which processes the signal detected by this detector is shortened. Furthermore, the substrates on which the detectors are mounted are housed in a housing as a unit (detector unit).

1 . A semiconductor radiation detector used for a nuclear medicine diagnostic apparatus comprising a semiconductor area where electric charge is generated through interaction with radiation, wherein an anode electrode and a cathode electrode are arranged opposed to each other sandwiching this semiconductor area and the distance between said anode electrode and cathode electrode or the thickness of said semiconductor area sandwiched between said anode electrode and cathode electrode is 0.2 to 2 mm.  
   
   
       2 . The semiconductor radiation detector according to  claim 1 , wherein said distance between the electrodes or the thickness of said semiconductor area is 0.5 to 1.5 mm.  
   
   
       3 . The semiconductor radiation detector according to  claim 1 , wherein the area of said electrode or the area of the semiconductor plane forming said electrodes is 4 to 120 mm 2 .  
   
   
       4 . A nuclear medicine diagnostic apparatus comprising: 
 a plurality of semiconductor areas where electric charge is generated through interaction with radiation;    a plurality of semiconductor radiation detectors including anode electrodes and cathode electrodes opposed to one another sandwiching these semiconductor areas;    a plurality of signal processing apparatuses provided for said plurality of semiconductor radiation detectors respectively, radiation detection signals from said corresponding semiconductor radiation detectors being input to each of the plurality of signal processing apparatuses;    a counting apparatus to which outputs from said plurality of signal processing apparatuses are input, the counting apparatus counts in pairs said outputs corresponding to pairs of said radiation detection signals detected within a set time; and    a tomographic information creation apparatus which creates tomographic information using the counting information output from said counting apparatus,    wherein the distance between said anode electrode and cathode electrode or the thickness of said semiconductor area of said semiconductor radiation detector sandwiched between said anode electrode and cathode electrode is 0.2 to 2 mm.    
   
   
       5 . The nuclear medicine diagnostic apparatus according to  claim 4 , wherein said distance between the electrodes or the thickness of said semiconductor area is 0.5 to 1.5 mm.  
   
   
       6 . The nuclear medicine diagnostic apparatus according to  claim 4 , wherein the area of said electrode or the area of the semiconductor plane forming said electrodes is 4 to 120 mm 2 .  
   
   
       7 . A nuclear medicine diagnostic apparatus comprising: 
 a plurality of semiconductor radiation detectors which receive radiation;    an integrated circuit which processes radiation detection signals output from said plurality of semiconductor radiation detectors;    a tomographic information creation apparatus which creates tomographic information using second information obtained based on first information output from said integrated circuit; and    a unit substrate including said plurality of semiconductor radiation detectors and said integrated circuit.    
   
   
       8 . The nuclear medicine diagnostic apparatus according to  claim 7 , further comprising a counting apparatus to which said first information from said integrated circuit is input, the counting apparatus counts in pairs said outputs corresponding to pairs of said radiation detection signals detected within a set time, 
 wherein said tomographic information creation apparatus creates tomographic information using the count information, which is said second information output from said counting apparatus.    
   
   
       9 . The nuclear medicine diagnostic apparatus according to  claim 7 , wherein said integrated circuit further comprising: 
 an analog integrated circuit which processes signals output from said semiconductor radiation detectors;    an AD converter which converts an analog signal which is the output of said analog integrated circuit to a digital signal; and    a digital integrated circuit which processes the AD-converted signal.    
   
   
       10 . The nuclear medicine diagnostic apparatus according to  claim 9 , wherein said semiconductor radiation detectors, said analog integrated circuit, said AD converter and said digital integrated circuit are arranged in that order from one end to the other end of said unit substrate in the longitudinal direction of said unit substrate.  
   
   
       11 . The nuclear medicine diagnostic apparatus according to  claim 9 , wherein said analog integrated circuit is provided with a function of amplifying signals and said digital integrated circuit is provided with a function of deciding radiation detection times.  
   
   
       12 . The nuclear medicine diagnostic apparatus according to  claim 7 , wherein said unit substrate comprises a first substrate and a second substrate, 
 said first substrate comprises said semiconductor radiation detectors, and    said second substrate comprises said integrated circuit.    
   
   
       13 . The nuclear medicine diagnostic apparatus according to  claim 9 , 
 wherein said unit substrate comprises a first substrate and a second substrate,    said first substrate comprises said semiconductor radiation detectors and said analog integrated circuit, and    said second substrate comprises said digital integrated circuit.    
   
   
       14 . The nuclear medicine diagnostic apparatus according to  claim 9 , 
 wherein said unit substrate comprises a first substrate, a second substrate and a third substrate,    said first substrate comprises semiconductor radiation detectors,    said second substrate comprises said analog integrated circuit, and    said third substrate comprises said digital integrated circuit.    
   
   
       15 . The nuclear medicine diagnostic apparatus according to any one of  claims 12  to  14 , wherein said first substrate and said second substrate are connected in a mutually detachable/attachable manner.  
   
   
       16 . The nuclear medicine diagnostic apparatus according to  claim 14 , wherein said second substrate and said third substrate are connected in a mutually detachable/attachable manner.  
   
   
       17 . The nuclear medicine diagnostic apparatus according to any one of  claims 12  to  14 , wherein said first substrate and said second substrate are connected in such a way that ends of both substrates are overlapped with each other.  
   
   
       18 . The nuclear medicine diagnostic apparatus according to  claim 7 , wherein said semiconductor radiation detectors are arranged on both sides of said unit substrate.  
   
   
       19 . The nuclear medicine diagnostic apparatus according to  claim 12 , wherein said semiconductor radiation detectors are arranged on both sides of said first substrate.  
   
   
       20 . The nuclear medicine diagnostic apparatus according to  claim 7 , further comprising a body of rotation and a bed on which an examinee is laid, 
 wherein said plurality of unit substrates are mounted on a support member provided in said body of rotation so as to revolve around said bed,    said semiconductor radiation detectors of said unit substrate are arranged on said bed side, and    said support member is provided with a collimator having a plurality of radiation passages opposed to said semiconductor radiation detectors and disposed closer to said bed than said semiconductor radiation detectors.    
   
   
       21 . The nuclear medicine diagnostic apparatus according to  claim 7 , further comprising a bed for supporting an examinee, wherein said plurality of unit substrates are arranged in such a way as to surround said bed and said semiconductor radiation detectors of said unit substrate are arranged on said bed side.  
   
   
       22 . A positron emission tomography apparatus comprising: 
 a plurality of semiconductor radiation detectors which receive radiation; and    an integrated circuit, which processes radiation detection signals output from said plurality of semiconductor radiation detectors,    wherein said integrated circuit outputs time information on radiation detection and identification information of said semiconductor radiation detectors which have detected radiation, and    a plurality of unit substrates including said plurality of semiconductor radiation detectors and said integrated circuit are provided.    
   
   
       23 . The positron emission tomography apparatus according to  claim 22 , wherein said integrated circuit comprises an analog integrated circuit which processes signals output from said semiconductor radiation detectors, an AD converter which converts an analog signal which is the output of said analog integrated circuit to a digital signal and a digital integrated circuit which processes the AD-converted signal.  
   
   
       24 . The positron emission tomography apparatus according to  claim 23 , wherein said semiconductor radiation detectors, said analog integrated circuit, said AD converter and said digital integrated circuit are arranged in that order from one end to the other end of said unit substrate in the longitudinal direction of said unit substrate.  
   
   
       25 . The positron emission tomography apparatus according to  claim 23 , wherein said analog integrated circuit is provided with a function of amplifying signals and said digital integrated circuit is provided with a function of generating said time information.  
   
   
       26 . The positron emission tomography apparatus according to  claim 22 , wherein said unit substrate comprises a first substrate and a second substrate, 
 said first substrate comprises said semiconductor radiation detectors, and    said second substrate comprises said integrated circuit.    
   
   
       27 . The positron emission tomography apparatus according to  claim 22 , wherein said semiconductor radiation detectors are arranged on both sides of said unit substrate.  
   
   
       28 . The positron emission tomography apparatus according to  claim 23 , 
 wherein said analog integrated circuit comprises a plurality of signal processing apparatuses which are provided for each of the semiconductor radiation detectors, and process said radiation detection signals, including an amplifier to which said radiation detection signals output from said semiconductor radiation detectors are input, and    said digital integrated circuit outputs said time information and said identification information based on the output of said signal processing apparatus.    
   
   
       29 . The positron emission tomography apparatus according to  claim 23 , 
 wherein said analog integrated circuit comprises a slow system including said amplifier and a peak value output apparatus which receives the output of this amplifier and outputs peak values of said radiation detection signals and a fast system including a timing detection apparatus to which said radiation detection signals from a position upstream of said amplifier are input, the timing detection apparatus outputs radiation detection timing signals, and    said digital integrated circuit comprises a time information generation apparatus provided for each semiconductor radiation detector for generating time information based on said radiation detection signals.    
   
   
       30 . The positron emission tomography apparatus according to  claim 29 , 
 wherein said digital integrated circuit further comprises an AD conversion control apparatus which identifies, when a signal is received from said time information creation apparatus, one of said position information and said identification information of said semiconductor radiation detectors connected to said time information creation apparatus and an information combination apparatus which combines said identified information, said time information and peak value information, and    said AD converter converts a peak value from the peak value output apparatus out of said peak value output apparatuses of a plurality of signal processing apparatuses included in said analog integrated circuit, which is determined by said information identified by said AD conversion control apparatus, to peak value information which is digital information and outputs the peak value information to said information combination apparatus.    
   
   
       31 . A semiconductor radiation detection apparatus comprising: 
 a plurality of semiconductor radiation detectors; and    an integrated circuit, which processes signals output from these semiconductor radiation detectors on a unit substrate,    wherein a plurality of signal lines for transmitting output signals of said semiconductor radiation detectors to said integrated circuit is provided on said unit substrate.    
   
   
       32 . The semiconductor radiation detection apparatus according to  claim 31 , wherein said integrated circuit comprising: 
 an analog integrated circuit which processes signals output from said semiconductor radiation detectors;    an AD converter which converts an analog signal which is the output of said analog integrated circuit to a digital signal; and    a digital integrated circuit which processes the AD-converted signal.    
   
   
       33 . The semiconductor radiation detection apparatus according to  claim 32 , wherein said semiconductor radiation detectors, said analog integrated circuit, said AD converter and said digital integrated circuit are arranged in that order from one end to the other end of said unit substrate in the longitudinal direction of said unit substrate.  
   
   
       34 . The semiconductor radiation detection apparatus according to  claim 31 , wherein said unit substrate comprises a first substrate and a second substrate, 
 said first substrate comprises said semiconductor radiation detectors, and    said second substrate comprises said integrated circuit.    
   
   
       35 . The semiconductor radiation detection apparatus according to  claim 34 , wherein said first substrate and said second substrate are connected in such a way that ends of both substrates are overlapped with each other in a mutually detachable/attachable manner.  
   
   
       36 . The semiconductor radiation detection apparatus according to  claim 31 , wherein said semiconductor radiation detectors are arranged on both sides of said unit substrate.  
   
   
       37 . A nuclear medicine diagnostic apparatus comprising: 
 a plurality of semiconductor radiation detectors which receive radiation;    an integrated circuit which processes radiation detection signals output from said plurality of semiconductor radiation detectors;    a tomographic information creation apparatus which creates tomographic information using second information obtained based on first information output from said integrated circuit; and    a plurality of detector units mounted on a support member in a detachable/attachable manner,    wherein each of said detector units comprises a plurality of unit substrates including said plurality of semiconductor radiation detectors and said integrated circuit, arranged in a frame in a detachable/attachable manner.    
   
   
       38 . The nuclear medicine diagnostic apparatus according to  claim 37 , further comprising a counting apparatus which receives said first information from said integrated circuit and counts in pairs said outputs corresponding to pairs of said radiation detection signals detected within a set time, 
 wherein said tomographic information creation apparatus creates tomographic information using the count information, which is said second information output from said counting apparatus.    
   
   
       39 . The nuclear medicine diagnostic apparatus according to  claim 37 , wherein said integrated circuit comprising: 
 an analog integrated circuit which processes signals output from said semiconductor radiation detectors;    an AD converter which converts an analog signal which is the output of said analog integrated circuit to a digital signal; and    a digital integrated circuit which processes the AD-converted signal.    
   
   
       40 . The nuclear medicine diagnostic apparatus according to  claim 39 , wherein said semiconductor radiation detectors, said analog integrated circuit, said AD converter and said digital integrated circuit are arranged in that order from one end to the other end of said unit substrate in the longitudinal direction of said unit substrate.  
   
   
       41 . The nuclear medicine diagnostic apparatus according to  claim 37 , wherein said unit substrate comprises a first substrate and a second substrate, 
 said first substrate comprises said semiconductor radiation detectors, and    said second substrate comprises said integrated circuit.    
   
   
       42 . The nuclear medicine diagnostic apparatus according to  claim 37 , wherein said frame comprises a plurality of guide members which guide said unit substrates.  
   
   
       43 . The nuclear medicine diagnostic apparatus according to  claim 37 , wherein said detection units are provided in said frame and comprise a power supply apparatus having a voltage boosting apparatus for boosting a voltage and wiring for applying a voltage from said power supply apparatus to each of said semiconductor radiation detectors of said unit substrates.  
   
   
       44 . The nuclear medicine diagnostic apparatus according to  claim 37  or  claim 43 , wherein said frame surrounds said plurality of unit substrates and this frame has light shielding properties.  
   
   
       45 . The nuclear medicine diagnostic apparatus according to  claim 39 , wherein another integrated circuit for combination which combines and processes information output from said digital integrated circuit of said plurality of unit substrates.  
   
   
       46 . A positron emission tomography apparatus comprising: 
 a plurality of semiconductor radiation detectors which receive radiation;    an integrated circuit which processes radiation detection signals output from said plurality of semiconductor radiation detectors; and    a plurality of detector units mounted on a support member in a detachable/attachable manner,    wherein each of said detector units comprises a plurality of unit substrates including said plurality of semiconductor radiation detectors and said integrated circuit, arranged in a frame in a detachable/attachable manner, and    said integrated circuit outputs time information of radiation detection and identification information of said semiconductor radiation detectors which have detected radiation.    
   
   
       47 . The positron emission tomography apparatus according to  claim 46 , wherein said integrated circuit comprises an analog integrated circuit which processes signals output from said semiconductor radiation detectors, an AD converter which converts an analog signal which is the output of said analog integrated circuit to a digital signal and a digital integrated circuit which processes the AD-converted signal.  
   
   
       48 . A detector unit comprising the plurality of semiconductor radiation detection apparatuses according to any one of  claims 31  to  36 , wherein said plurality of semiconductor radiation detection apparatuses are arranged in a frame in a detachable/attachable manner.  
   
   
       49 . The detector unit according to  claim 48 , wherein said frame is provided with a guide apparatus which guides said semiconductor radiation detection apparatuses and said guide apparatus holds said semiconductor radiation detection apparatuses in such a way that a plurality of semiconductor radiation detection apparatuses do not overlap with one another in a certain direction.  
   
   
       50 . The detector unit according to  claim 48 , further comprising a power supply apparatus which is mounted in said frame and has a voltage boosting apparatus for boosting a voltage; and 
 wiring which applies voltages from said power supply apparatus to said semiconductor radiation detectors of said unit substrate respectively.    
   
   
       51 . The detector unit according to  claim 48 , wherein said frame surrounds said plurality of unit substrates and this frame has light shielding properties.  
   
   
       52 . The detector unit according to  claim 48 , wherein another integrated circuit for combination which combines and processes information output from said digital integrated circuits of said plurality of unit substrates is provided in said frame.  
   
   
       53 . A nuclear medicine diagnostic apparatus comprising: 
 a plurality of semiconductor radiation detectors which receive radiation;    an integrated circuit which processes radiation detection signals output from said plurality of semiconductor radiation detectors;    a tomographic information creation apparatus which creates tomographic information using second information obtained based on first information output from said integrated circuit;    a frame in which said plurality of semiconductor radiation detectors are mounted;    a power supply apparatus which is mounted in said frame and has a voltage boosting apparatus for boosting a voltage; and    wiring which applies voltages to said semiconductor radiation detectors respectively.    
   
   
       54 . The nuclear medicine diagnostic apparatus according to  claim 53 , wherein a plurality of unit substrates including said plurality of semiconductor radiation detectors and said integrated circuit are mounted in said frame.  
   
   
       55 . The nuclear medicine diagnostic apparatus according to  claim 53 , further comprising a counting apparatus to which said first information from said integrated circuit is input, the counting apparatus counts in pairs said outputs corresponding to pairs of said radiation detection signals detected within a set time, 
 wherein said tomographic information creation apparatus creates tomographic information using the counting information which is said second information output from said counting apparatus.