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LOW LEVEL MEASURE & SOURCE A Greater Measure of Confidence www.keithley.com 1.888.KEITHLEY (U.S. only)

• 1 0f a r esolution
• 5 ½-digit resolution
• < 200µV burden voltage
• al ternating Voltage method ohms measurements
• au tomated voltage sweeps for I-V characterization
• fl oating measurements up to 500V
• up t o 1000 readings/second
• bu ilt-in Model 486 and 487 emulation mode
• I EEE-488 and rs- 232 interfaces
• ana log output
• D igital I/ o The 5½-digit Model 6487 Picoammeter/Voltage Source improves on the measurement capability of the award-winning Model 6485, and adds a high resolution 500V source It provides higher accuracy and faster rise times than the 6485, as well as a damping function for use with capaci - tive devices With eight current measurement ranges and high speed autoranging, this cost- effective instrument can measure currents from 20fA to 20mA, take measure men ts at speeds up to 1000 readings per s econd, and source voltage from 200µV to 505V . T he Model 6487’s 10fA resolution, superior sen- sitivity, voltage sweeping, and Alternating Voltage resistance measurements make it well suited for characterizing low current devices Using the latest current measurement technology, it is sig- nificantly less expensive than other instruments that p erform similar functions, such as optical power meters, tera-ohmmeters, competitive picoammeters, or user-designed solutions With a price that’s comparable to a high-end DMM, the Model 6487 makes picoamp-level measurements affordable for virtually any laboratory or production floor lo w Voltage bu rden and Higher ac curacy While DMMs typically employ shunt ammeter circuitry to measure current, the Model 6487 is a feed - back picoammeter . This design reduces voltage burden by several orders of magnitude, resulting in a voltage burden of less than 200µV on the lower measurement ranges . The low voltage burden makes the Model 6487 function much more like an ideal ammeter than a DMM, so it can make current measurements with high accuracy, even in circuits with very low source voltages su ccessor to the Model 487 The Model 6487 builds on the strengths of one of Keithley’s most popular picoammeters, the Model 487, offering an additional 20mA measurement range, as well as much higher measurement speeds, up to 1000 readings per second It simplifies device characterization with built-in voltage sweeping capability and the Alternating Voltage method for high resistances A t ime-stamped 3000-reading data buffer pro - vides minimum, maximum, and standard devia - tion statistics . A built-in emulation mode makes it possible to control the Model 6487 with any custom code written to control the Model 487 fe atures that Expand Test and Measurement fl exibility
• D irect resistance measurements. Optimized for resistances from 50 W to 5×1014W using the Source Voltage/Measure Current method
• A lternating Voltage method resistance measurements. This method improves resistance measurements on devices with high background current or high noise . It extends the measurable resistance range up to 1016W .
• 5 00V overload protection. This high overload protection and a robust design let the Model 6487 to lerate abusive overflows, including accidentally shorting the voltage source directly into the ammeter . Model 487 Model 6487 Current Ranges 2 nA–2 mA 2 nA–20 mA Voltage Burden 200 µV 200 µV (1 mV on 20 mA range) Reading Rate Up to 180/s Up to 1000/s Voltage Sweeps No Yes Alternating Voltage Ohms No Yes Analog Output Yes (non-inverting) Yes (inverting) Storage Buffer 512 points 3000 points Best V Source Resolution 1 mV 0 mV

6487 Picoammeter/Voltage Source

Measures low currents and high resistances quickly, accurately, and economically Measures low currents and high resistances quickly, accurately, and economically

LOW LEVEL MEASURE & SOURCE www.keithley.com 1.888.KEITHLEY (U.S. only) A Greater Measure of Confidence

• R ear panel triax input. This allows the picoammeter to be used in floating operation, up to 500V . When not floating, the addition of a triax to BNC a dapter allows inexpensive, easy-to-use BNC cables to be employed, rather than more expensive triaxial cables .
• R S-232 and IEEE-488 interfaces. These interfaces make it easy to integrate the Model 6487 into automated test and measurement systems .
• S caled voltage analog output. This output allows the Model 6487 to transmit measurement results to devices like DMMs, data acquisition cards, oscilloscopes, or strip chart recorders .
• B uilt-in Trigger Link interface. The Trigger Link interface simplifies synchronizing the Model 6487 with other instruments and voltage sources . This interface combines six independent selectable trigger lines on a single connector for simple, direct control over all instruments in a system .
• D isplay on/off switch. For research on light-sensitive components, such as measuring the dark currents of photodiodes or I-V me asurements on unpackaged semiconductors, the front panel display can be switched off to avoid introducing light that could significantly reduce the accuracy of the results
• O ne-touch front panel design. Functions can be configured easily with the push of a button, without complicated function menus . a br oad ran ge of low C urrent ap plications Wafer-le vel Photodiode Testing The Model 6487 Picoammeter/Voltage Source can be paired with a calibrated light source and a probing fixture to create a cost-effective photodiode test system Multiple Model 6487s can be con- nected to the DUT’s probe pads to provide photocurrent readings or, with the addition of a switch matrix, one pico a mmeter can take current measurements from multiple pads . In the first step of the measurement p rocess, performed in total darkness, the Model 6487 produces a voltage sweep and then measures the resulting dark current In the second step, a voltage bias is applied and the result- ing photocurrent is meas u red while the light level is increased in calibrated steps . The same basic test configuration can be used for testing positive intrinsic negative (PIN) and avalanche photodiodes (APDs) The 6487’s high resolution on the 10V source range provides superior sweeping and biasing when small biases are required The 500V source capability is necessary to bias APDs . or dering Information

6487 Picoammeter/

V oltage sou rce a ccessories s upplied Ca-1 86-1b G round Connection Cable, ba nana to s crew-lu g CaP -31 P rotective sh ield/ Cap (3-lug) Cs- 459 s a fety Interlock Plug 7078-TrX low Noise Triax Input Cable, 1m (3 ft) 8607 H igh Voltage ba nana Cable se t for Voltage s ource out put Photo Diode AmmeterVsource Calibrated Light Source Probe Needles Wafer Pads Probe Needles

• res istance/resistivity measurements
• be am monitoring and radiation monitoring
• le akage current testing in insulators, switches, relays, and other components
• G alvanic coupling measurements
• I -V characterization on semiconductor and optoelectronic devices fi ber alignment
• C ircuit test and analysis in DC l f c ircuits
• se nsor characterization
• C apacitor leakage

6487 Picoammeter/ Voltage Source

Measures low currents and high resistances quickly, accurately, and economically Measures low currents and high resistances quickly, accurately, and economically

LOW LEVEL MEASURE & SOURCE A Greater Measure of Confidence www.keithley.com 1.888.KEITHLEY (U.S. only) When do you need a picoammeter? Measuring low DC currents often demands a lot more than a digital multimeter can deliver. Generally, DMMs lack the sensitivity required to measure currents less than 100nA. Even at higher currents, a DMM’s input voltage drop (voltage burden) of hun d reds of millivolts can make accurate current measurements impossible. Electrometers can measure low currents very accu r ately, but the circuitry needed to measure extremely low currents, combined with functions like voltage, resistance, and charge measure m ent, can increase an electrom- e ter’s cost significantly. The Model

6487 Picoammeter/Voltage

Source combines the economy and ease of use of a DMM with low current sensitivity near that of an electrometer. Monitoring and Control of foc used Ion bea m Currents In semiconductor fabrication, focused ion beam systems are often used for nanometer-scale imaging, micromachining, and mapping . Careful monitoring of the magnitude of the beam current with an ion detector is critical . The ion detector generates a secondary current that’s proportional to the current of the primary ion beam . When this secondary current is measured, it can be used to control the intensity of the primary beam . However, this secondary current is very low, often just a few picoamps, so the instrumentation measuring it must provide high measurement accuracy and repeat - ability, as well as sub-picoamp resolution . The Model 6487’s wide measurement range and 5½-digit resolution make it ideal for this application . Signal connections to the Model 6487 are made through the instrument’s triax connector . Often, a detector may require high voltage to attract ions, making the 6487’s 500V source a necessity . 6487 Picoammeter/Voltage Source Ion Detector Ion Beam IM Voltage SourceMetal Shield R HI LO Ammeter HI LO Vsource aCCEssorI E s aVaIl ablE High re sistance Measurements The Model 6487 Picoammeter can be used to measure high resistances (>1GW) in applications such as insulation resistance testing . A c onstant voltage is placed in series with the unknown resistance and the picoammeter The voltage drop across the picoammeter is negligible, so all the voltage appears across the unknown resistance The resulting current is measured by the picoammeter and the resistance is calculated using Ohm’s Law (R = V/I) To prevent generated current due to electrostatic interference, the unknown resistance is housed in a shielded test fixture A small series resistor may be added to reduce noise if the un k nown resistor has high stray capacitance across it sEr VICEs aVaIl ablE 6487-3Y-EW 1 -year factory warranty extended to 3 years from date of shipment C/6487-3Y-ISO 3 ( ISO-17025 accredited) calibrations within 3 years of purchase* *Not available in all countries CablEs 6517-ILC-3 I nterlock Cable for 8009 Resistivity Test Fixture 7007-1 S hielded IEEE-488 Cable, 1m (3 .3 f 7007-2 S hielded IEEE-488 Cable, 2m (6 .6 f 7007-4 S hielded IEEE-488 Cable, 4m (13 .1 f 7078-TRX-10 L ow Noise Triax Cable, 3 .0 m (10 ft) 7078-TRX-20 L ow Noise Triax Cable, 6 .0 m (20 ft) 8501-* T rigger Link Cable with male Micro-DIN connectors at each end, 1m or 2m (3 .3 f t or 6 .6 f aDa PTE rs 237-TRX-BAR T riax Barrel 7078-TRX-BNC Triax-to-BNC A dapter TEsT fIXT urEs

8009 R esistivity Test Fixture

4288-* S ingle or Dual Fixed Rack Mounting Kit GPIb INTE rfaCEs KPCI-488LPA I EEE-488 Interface/Controller for the PCI Bus KUSB-488B I EEE-488 USB-to-GPIB Interface Adapter Measures low currents and high resistances quickly, accurately, and economically Measures low currents and high resistances quickly, accurately, and economically

LOW LEVEL MEASURE & SOURCE www.keithley.com 1.888.KEITHLEY (U.S. only) A Greater Measure of Confidence GENEral AMMETER INPUT CONNECTOR: Three lug triaxial on rear panel A NALOG OUTPUT CONNECTOR: Two banana jacks on rear panel V OLTAGE SOURCE OUTPUT CONNECTOR: Two banana jacks on rear panel . I NTERLOCK CONNECTOR: 4 pin DIN T RIGGER LINE: Available, see manual for usage . DI SPLAy: 12 character vacuum fluorescent . D IGITAL FILTER: Median and averaging (selectable from 2 to 100 readings) . R ANGING: Automatic or manual . A UTORANGING TIME 3: <250ms (analog filter off, 1PLC) . O VERRANGE INDICATION: Display reads “OVRFLOW .” C ONVERSION TIME: Selectable 0 1PLC to 60PLC (50PLC under 50Hz operation) . (Adjustable from 200µs to 1s) READING RATE: To internal buffer 000 readings/second 1 To IEEE-488 bus 00 readings/second 1, 2 BUFFER: Stores up to 3000 readings . P ROGRAMS: Provide front panel access to IEEE address, choice of engineering units or scientific notation, and digital calibration . E MC: C onforms with European Union Directive 89/336/ EEC, EN61326-1 . S AFET y: C onforms with European Union Directive 73/23/ EEC, EN61010-1, CAT I . EN VIRONMENT: Operating: 0°–50°C; relative humidity 70% non- condensing, up to 35°C . Above 35°C, derate humidity by 3% for each °C . St orage: –10°C to +65°C . W ARM-UP: 1 hour to rated accuracy (see manual for rec - ommended procedure) . P OWER: 100–120V or 220–240V, 50–60Hz, (50VA) . P HySI CAL: Case Dimensions: 90mm high × 214mm wide × 369mm deep (3½ in . W orking Dimensions: From front of case to rear including power cord and IEEE-488 connector: 394mm (15 inches) . N ET WEIGHT: <4 .7 k g (<10 .3 l bs) . NoT E s 1 . 0 .0 1PLC, digital filters off, front panel off, auto zero off . 2 . B inary transfer mode . IEEE-488 .1 . 3 . M easured from trigger in to meter complete . T ypical ana log 5½ Digit a c curacy ( 1 Year) 1 ri se Time (10% to 90%) 3 D efault ± (% rdg. + o ffset) T ypical D amping4 r a nge r e solution 1 8°–28°C, 0–70% rH r Ms Noise 2 o f f o n 2 n A 1 0 f A 0 .3 % + 4 00 fA 2 0 fA 4 m s 8 0 ms n A f A 0 .2 % + 1 p A 0 fA 4 m s 0 ms n A p A 0 .1 5% + 0 pA 1 p A 00 µs 1 m s µ A p A 0 .1 5% + 00 pA 1 p A 00 µs 1 m s µ A p A 0 .1 % + 1 n A 00 pA 10 µs 10 µs µ A n A 0 .1 % + 0 nA 00 pA 10 µs 10 µs m A n A 0 .1 % + 00 nA 0 nA 10 µs 10 µs m A n A 0 .1 % + 1 µ A 0 nA 10 µs 10 µs TEMPERATURE COEFFICIENT: 0°–18°C & 2 8°–50°C . For each °C, add 0 .1 × (% rdg + o ffset) to accuracy spec . IN PUT VO LTAGE BU RDEN: <200µV on all ranges except <1mV on 20mA r ange . MA XIMUM IN PUT CA PACITANCE: S table to 10nF on all nA ranges and 2µA r ange; 1µF on 20µA and 200µA ranges, and on mA ranges . M AXIMUM C ONTINUOUS I NPUT V OLTAGE: 505 VDC . N MRR1: (50 or 60Hz): 60dB . I SOLATION (Ammeter Common or Voltage Source to chassis): Typically >1 ×1011W in p arallel with <1nF . M AXIMUM COMMON MODE VOLTAGE (between chassis and voltage source or a mmeter): 505 VDC . A NALOG OUTPUT: Scaled voltage output (inverting 2V full scale on all ranges): 2 .5 % ±2mV . A NALOG OUTPUT IMPEDANCE 3: <100W, DC–2kHz . V OLTAGE SOURCE: a cc uracy 5 N oise T ypical T ypical r a nge s t ep si ze ± (% prog. + o ffset) ( p-p) T emperature r i se Time 6, 8 f all Time 7, 8 ( Max.) ( typical) 1 8°–28°C, 0–70% r. H. 0 .1–10 Hz C oefficient ( 10%–90%) ( 90%–10%) ± 10 .1 00 2 00 µV 0 .1 % + 1 m V < 50 µV ( 0 .0 05% + 2 0 µV)/°C 2 50 µs 1 50 µs 50 .5 1 m V 0 .1 % + 4 m V 150 µV 0 .0 05% + 200 µV)/°C 50 µs 00 µs 505 .0 0 mV 0 .1 5% + 40 mV 1 .5 m V 0 .0 08% + 2 m V)/°C 4 .5 m s 1 m s SELECTABLE CURRENT LIMIT: 2 .5 mA, 250µA, 25µA for 50V and 500V ranges, 25mA additional limit for 10V range . All current lim - its are –20%/+35% of nominal . W IDEBAND NOISE 9: <30mVp-p 0 .1H z–20MHz . TyP ICAL TIME STABILIT y: ±(0 .0 03% + 1mV) over 24 hours at constant temperature (within 1°C, between 18°–28°C, after 5 minute settling) . OU TPUT RESISTANCE: <2 .5W . V OLTAGE SWEEPS: Supports linear voltage sweeps on fixed source range, one current or resistance measurement per step . Maximum sweep rate: 200 steps per second . Maximum step count 3000 Optional delay between step and measure . RE SISTANCE ME ASUREMENT (V/I): Used with voltage source; resistance calculated from voltage setting and measured current . Accuracy is based on voltage source accuracy plus ammeter accuracy . Typical accuracy better than 0 .6 % for readings between 1k W and 1TW . A LTERNATING VOLTAGE RESISTANCE MEASUREMENT: O ffers alternating voltage resistance measurements for resistances from 109W to 1015W . Alternates between 0V and user-selectable voltage up to ±505V . N oT E s 1 . A t 1 PLC – limited to 60 rdgs/s under this condition . 2 . A t 6 PLC, 1 standard deviation, 100 readings, filter off, capped input – limited to 10 rdgs/sec under this condition . 3 . M easured at analog output with resistive load >2k W . 4 . M aximum rise time can be up to 25% greater . 5 . A ccuracy does not include output resistance/load regulation . 6 . R ise Time is from 0V to ± full-scale voltage (increasing magnitude) . 7 . F all Time is from ± full-scale voltage to 0V (decreasing magnitude) . 8 . F or capacitive loads, add C· ∆V/ILimit to rise time, and C· ∆V/1mA to fall time . 9 . M easured with LO connected to chassis ground . rEM oTE o PE raTI o N IEEE-488 BUS IMPLEMENTATION: SCPI (IEEE-488 .2, SCPI-1996 .0 ); DDC (IEEE-488 .1 ) . L ANGUAGE EMULATION: Keithley Model 486/487 e mulation via DDC mode . R S-232 IMPLEMENTATION: Supports: SCPI 1996 .0 . B aud Rates: 300, 600, 1200, 2400, 4800, 9600, 19 .2 38 .4 k, 57 k . P rotocols: Xon/Xoff, 7 or 8 bit ASCII, parity-odd/even/ none . C onnector: DB-9 TXD/RXD/GND .