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Electron Multipliers [2.5 Mb/Pdf] PRODUCT LINE-UP Electron multipliers are mainly used as positive/negative ion detectors. They are also useful for detecting and measuring vacuum UV rays and soft X-rays. Hamamatsu electron multipliers have a high gain (multiplication factor) yet low dark current, allowing operation in photon counting mode to detect and measure extremely small incoming particles and their energy. This means our Hamamatsu electron multipliers are ideal for electron spectroscopy, vacuum UV spectroscopy such as ESCA (electron spectroscopy for chemical analysis) and Auger electron spectroscopy as well as mass spectroscopy and field-ion microscopy. Dynode Characteristics Anode to Rise Dark Detection Number Input Supply Gain Total all other Type No. Structure of Material aperture time current ion electrode voltage resistance polarity stages size Typ. Typ. Typ. capacitance (mm) (V) (ns) (pA) (MΩ) (pF) R4146-10 Linear-focused 18 Cu-BeO 8 × 1 -1800 1 × 107 3.5 0.1 21 Positive 4.0 2 R6985-80 Box-and-line 19 Al2O3 11 -1900 1 × 106 4.5 0.1 17.15 Positive/negative 1.8 R8811 Circular-cage 13 Al2O3 3 -1500 1 × 105 1.6 0.1 13 Positive 0.8 R2362 Coarse mesh 23 Cu-BeO 20 -2700 1 × 106 3.5 1 23 Positive 23 R5150-10 Box-and-line 17 Cu-BeO 8 -1800 1 × 107 1.7 0.1 19.5 Positive 4.0 1 R474 Box-and-grid 16 Cu-BeO 8 × 6 -1500 1 × 106 11.8 0.1 16 Positive 5.0 1 R515 Box-and-grid 16 Cu-BeO 8 × 6 -1500 1 × 106 11.8 0.1 16 Positive 4.0 R596 Box-and-grid 16 Cu-BeO 12 × 10 -1500 2 × 106 12.6 0.1 16 Positive 9.0 R595 Box-and-grid 20 Cu-BeO 12 × 10 -1500 4 × 106 14.4 0.1 20 Positive 9.0 11 MΩ resistor is connected between Dynode 1 and Dynode 2. Remove 1 MΩ resistor connected between Dynode 1 and Dynode 2 when Dynode 1 is used as Faraday cup. 2Supply a negative potential to the conversion dynode when detecting positive ions. Supply a positive potential when detecting negative ions. R4146-10 R6985-80 58 ± 1 IFeatures × IFeatures INPUT APERTURE (8 1) 0.2 INPUT APERTURE ± Thin configuration 35.0 ± 0.5 Conversion dynode 0.2 ± ± ± Can be stacked side-by-side 12.0 0.2 19.0 0.2 11.0 6.0 Mounting plate potential 0.1 Mounting plate potential 0.1 21.0 ± 0.2 Rear plate: GND ± × ± 2 2.2 FRONT PLATE 1.1 Front plate: -HV 3.0 FRONT PLATE CONVERSION DYNODE Rear plate: GND RESISTORS 1 +0 -0.2 ± 1.0 ± 93 56.9 20.0 ± 0.5 0.5 ± 71.8 1 30.0 1 × ± ELECTRON 2 1 REAR PLATE 1 ± CONVERSION 15 MULTIPLYING 22.0 ± 0.5 20.0 ± 0.5 DYNODE PIN SECTION 12 2 × 1 HV PIN REAR PLATE OUTPUT PIN 11.0 ± 0.2 0.5 0.5 ± ± × 30.0 2 2.2 50.0 ± ± (Unit: mm) (Unit: mm) 12.0 0.2 19.0 0.2 GND PIN OUTPUT PIN 2 × 3.1 TPMHA0588EB TPMHA0587EB R8811 R2362 IFeatures 19.5 ± 0.5 IFeatures 10 Small, lightweight INPUT APERTURE Wide detection area 50 ± 1 ± Includes Faraday cup 44.0 0.5 10 Mounting plate potential 0.5 0.2 ± Mounting plate potential Front plate: -HV ± × 20.0 2 3.2 0.2 20.0 Front plate (case): GND ± INPUT 3 FRONT PLATE APERTURE FRONT PLATE RESISTORS 0.5 ± 60 MAX. 20.0 OUTPUT LEAD 3 × 1.5 HV LEAD REAR PLATE OUTPUT PIN GND PIN 0.5 1 ± ± 30 20.0 HV PIN (Unit: mm) (Unit: mm) FARADAY CUP LEAD TPMHA0608EA TPMHA0609EA 2 Electron multipliers listed in this catalog are standard products. We welcome requests for custom products. Please contact us with your needs. GGain characteristics TPMHB0929EC 108 Maximum ratings 4 Anode 7 4 Conversion Faraday Average Bake-out Operating 10 Operating to first voltage cup anode temperature vacuum gain dynode voltage current voltage 1×10-4 Pa level 6 (V) (kV) (V) (µA) (°C) (Pa) 10 1 × 108 2500 — — 10 350 1 × 10-2 8 2 3 -2 1 × 10 3000 ±10 — 10 — 1 × 10 105 5 × 106 2000 — -200 10 350 1 × 10-2 GAIN 1 × 108 4000 — — 10 350 1 × 10-2 104 × 8 × -2 R595 1 10 3500 — — 10 350 1 10 R596 1 × 108 4000 — -100 10 350 1 × 10-2 R474, R515 R4146-10 1 × 108 4000 — -100 10 350 1 × 10-2 103 R8810 R5150-10 8 -2 1 × 10 4000 — — 10 350 1 × 10 R2362 × 8 × -2 R6985-80 1 10 5000 — — 10 350 1 10 102 1000 2000 3000 4000 3Do not perform baking on the R6985-80. 4Use a supply voltage that does not cause the operating gain to exceed its maximum rating. SUPPLY VOLTAGE (V) R5150-10 R474 R515 IFeatures 34.0 ± 0.5 IFeatures IFeatures 20.0 ± 0.5 INPUT ± 0.5 20.0 0.5 6.0 ± 0.2 APERTURE ± 8.0 ± 0.2 0.2 Easy handling First dynode usable ± First dynode usable 6.0 ± 0.2 8.0 (contained in a case) as Faraday cup 17.0 as Faraday cup 0.5 0.2 ± 0.5 ± ± INPUT 8.0 26.0 Mounting plate INPUT APERTURE Mounting plate 26.0 APERTURE Mounting plate × 2 3.2 4 potential potential FRONT PLATE 4 2 × 3.2 potential FRONT PLATE Shield case: GND SHIELD CASE Front plate: -HV RESISTORS Front plate: -HV HAMAMATSU Rear plate: GND RESISTORS 0.5 ± 2 ± 90 MIN. 2 66.0 ± 73 MAX. 70 79 82 MAX. 90 MAX. REAR PLATE 3 × 1.2 SEMI- LEAD LENGTH FLEXIBLE 0.5 1 LEAD ± 12.0 ± 0.5 × OUTPUT PIN 2 1 OUTPUT PIN 3 × 0.3 10.0 DY2 DY2 PIN 0.5 GND PIN HV PIN (DY1) ± 2 × 3.2 21.0 0.5 HV PIN ± OUTPUT 34.0 ± 0.5 HV (DY1) (Unit: mm) (Unit: mm) 39 MAX. 11.0 (Unit: mm) TPMHA0610EA TPMHA0611EA TPMHA0612EA R596 R595 ± 10.0 ± 0.2 10.0 0.2 IFeatures INPUT APERTURE IFeatures INPUT APERTURE Wide detection area High gain 0.5 0.2 0.5 0.2 ± ± ± ± Wide detection area 12.0 42.0 12.0 Mounting plate potential 42.0 2 × 4.2 2 × 4.2 6.5 FRONT PLATE Front plate: -HV 6.5 FRONT PLATE Mounting plate potential Rear plate: GND Front plate: -HV Rear plate: GND 2 ± 2 ± RESISTORS 111 120 MAX. 131 140 MAX. 130 MAX. 150 MAX. RESISTORS 0.5 ± 0.5 ± 10.0 10.0 7 × 1.5 1 REAR PLATE 7 × 1.5 1 GND PIN GND PIN REAR PLATE OUTPUT PIN OUTPUT PIN 0.5 0.5 1 ± ± ± 1 0.5 0.5 ± ± ± 3 × 3.5 50 (Unit: mm) 3 × 3.5 (Unit: mm) 50 44.0 30.0 44.0 30.0 HV PIN (DY1) TPMHA0613EA HV PIN (DY1) TPMHA0614EA 3 TECHNICAL INFORMATION CONSTRUCTION AND OPERATING PRINCIPLE 4) Box-and-line type An electron multiplier mainly consists of a input aperture, an The structure of this type consists of a electron multiplying section (dynode section), an anode, and combination of box-and-grid and voltage-divider resistors. linear-focus dynodes. This type offers Electron multipliers operate in a vacuum and guide the particles better time response than the box- or rays (positive/negative ions, vacuum UV rays, soft X-rays, and-grid type and higher ion collection etc.) so as to enter the first dynode. The first dynode is excited efficiency than the linear-focused type. by such particles or rays and emits secondary electrons from its TPMHC0256EA surface. These electrons are multiplied in cascade by the 5) Coarse mesh type second and following dynodes and a cluster of secondary This type has a structure of wire ION electrons finally reaches the anode and is output as a signal. dynodes with a triangle cross section stacked in the form of a mesh. This ELECTRON MULTIPLYING SECTION structure ensures excellent linearity Electron multipliers operate with a high S/N ratio since they have low and is less affected by magnetic fields. noise and high gain. This low noise and high gain is achieved by an Compared to other dynode structures electron multiplying section made up of 13 to 23 stages of electrodes this type makes it easier to design a 1 mm called dynodes. Before using an electron multiplier, it is first exposed detector with a wider effective area. TPMHC0257EA to air once and then installed in equipment. The dynode therefore uses materials that exhibit stable characteristics and less CONVERSION DYNODE (CD) deterioration even when exposed to air. Hamamatsu electron The acceleration of ions differs according to their mass. The multipliers are designed and produced based on our advanced speed at which ions enter the first dynode affects the secondary technology for photomultiplier tubes and so have high performance. electron emission efficiency, so the higher the speed, the better The dynode structures in the electron multiplying section are the efficiency. When detecting ions with a large mass (for described below. example, polymer compounds), the ions must be accelerated by a high potential to obtain a speed great enough to maintain a 1) Box-and-grid type sufficient secondary electron emission efficiency. Conversion This type consists of a train of quarter cylindrical dynodes and dynodes (CD) are usually used to give a high potential to such offers good electron collection efficiency and excellent ions with a large mass. uniformity. This type is likely to resist voltage breakdown even TPMHB0934EA Sample: Per fluore tri-buthyl amine when a high voltage is supplied.
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