This literature was published years prior to the establishment of Agilent Technologies as a company independent from Hewlett-Packard and describes products or services now available through Agilent. It may also refer to products/services no longer supported by Agilent. We regret any inconvenience caused by obsolete information. For the latest information on HEWLETT Agilent's test and measurement products go to: PACKARD www.agilent.com find products Or in the US, call Agilent Technologies at 1-800-452-4844 (8am-8pm EST) DC Characterization Power Devices of Semiconductor Product Note 4142B-1 - Practical Applications Using the HP4142B Modular DC Source/Monitor Table of Contents 1 1. Introduction .................................................................................................. 2 2. Application Examples ................................................................................... 2 2.1 Automatic Extraction of Parameters.. ...................................................... 2 2.1.1. Automatic Measurements with a Module Selector.. ........................ 2.1.2 Enhancing Automatic Measurements by External Relay Control .... 4 6 2.2 Extending the Measurement Range ......................................................... 6 2.2.1. 2000 V Measurement ..................................................................... 8 2.2.2. lOA/20V Measurement.. ................................................................ 10 2.2.3. 20A/ 1OV Measurement .................................................................. 2.2.4. High Power Measurement (250 mA x 100 V, 125 mA x 200 V) ...... .12 Appendix Subprograms used in 2.1.1 . . . .. . . . . . . . . . . . .. . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . .. . . . . . . . . . . . .. . . . . . . . . 14 1 1. Introduction The HP 4142B Modular DC Source Monitor is a high speed, highly accurate, computercontrolled dc parametric measurement instrument for characterizing semiconductor devices. This product note uses an HP 4142B to show practical measurement examples that characterize semiconductor power devices. Model number HP 4 I420A Source Monitor Unit HP414215 Source Monitor Unit / Acronym / 1-V range HPSMU 4OpV-2OOV. MPSMU 4OpV- 1. The HP 4142B plug-in High Current HCU Unit HP41423A modules for measurements I OOV, 20fA- 4OpV-IOV, 2 mV- HP41425A Analog Feedback Unit You can mix and match different plug-in modules for unique application requmments Example configuration devices on a wafer. I A I OOmA HP 4 l422A HP 4 I424A Table 20fA- - of 20j1A-IOA I OOOV, 2 pA- I OmA , 2 2. Application 2.1 Automatic Parameters Examples Extraction of 2.1.1. Automatic Measurements with a Module Selector When you extract the dc parameters of a power device, you need to change the configuration for almost every parameter since each parameter requires a unique configuration of the instruments and measurement circuit. However, if the configuration can be changed automatically, the dc parameters can also be extracted automatically. The HP 16087A Module Selector lets you change the configuration programmatically, thus freeing you from cumbersome configuration changes. This section shows a versatile example for automatically extracting the dc parameters of a MOSFET. The setups needed to extract each parameter are shown in Figure 1. The circuits in Figure 2 are functionally the same as in Figure 1, but electronically different. The setup in Figure 2 uses the module selector to automatically change the configuration. An example of automatically extracting parameters by using the module selector is shown in Figure 3. The program listing of this example is shown in Figure 4. BVdss. Parameter ldss circut Figure 1. Parameters measurement circuits MODULE f,Du for MOSFET and SELECTOR ,HC:+- ~ Figure 2. You can easily change the connection of measurement modules with the module se!ector l*** Parameter Jds(on) ?ds(on) i/th Jth (by JfS lgss Bvdss ldss AFU) Measurement = 5.02 2.51 4.98 3.512 .913 4.17E-11 493.5 .023216 CMOS) **a* (V) (ohm) (VI (V) (S) (A) (V) (A) (Id=2A, (Id=2A, (Vd=lBV) (Vd=lBV, (Vg=20V) (Id=lBmA) (Vd=320V) Vg=lSV) Vg=lSJ) Id=lmA) [ HCU [ HCU r HCU 1 MPSMU t HCU [ MPSHU [ HVU [ HVU FIgwe 3. Simple for auto extraction 1 1 I 1 1 1 1 1 measurement results of parameters. 3 Let’s examine the benefits of using an HP 4142B to measure each parameter. For the ON state resistance measurement of a power MOSFET, a source of high current and a monitor for high resolution voltage are necessary. The HP 41422A High Current Source/Monitor Unit (HCU) can force a maximum current of 1OA and can make high resolution measurements with a minimum voltage of 4OpV. Therefore, the HCU can make precision measurements of the ON state resistance, which is an important parameter of power MOSFETs. There are several ways to extract the threshold voltage (Vth) of a MOSFET. In this example, two methods are used. The first method measures the J%l-Vg characteristics, then draws a regression line and extracts as threshold voltage the X-axis value at the cross point of the regression line and the X-axis. The second method is much faster. An HP 41425A Analog Feedback Unit (AFU) and two HP 41421B Source/Monitor Units (SMUs) are connected in a feedback loop. The AFU monitors the output voltage of one SMU, which is connected to the gate of the MOSFET, and monitors the current of the other SMU, which is connected to the drain. When the drain current reaches a user-specified value, the voltage value of the gate (Vth) is extracted. Vth is usually measured by a combination of a High Power SMU (HPSMU) and a Medium Power SMU (MPSMU). To measure the leakage current of a high power device, high voltage output and low current 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 OPTION %ASE 1 COM /Meas/ @Hp4142,INTEGER Hcu,Hvu,Smu,Hpsmu COM /Disp/ Vth,Vth - afu,Yfs,Igss,Bvdss,Idss,Vdson,Rds( ! ASSIGN @Hp4142 TO 723 Hpsmu=2 Smu=3 Hcu=5 Hvu=7 ! ! slot slot 2 3 ! slot 7 ! slot 5 ! Hcu connect Vds-on VthSmu connect 1gss Vth afu Hvu-connect Idss Bvdss Disp res mos END - 50-90 Initialization. 110-130 Connect HCU and measure Vds (on), Rds (on), Vth, yfs. 140-160 Connect SMU and measure Vth with AFU. 170-190 Connect HVU and measure Idss and BVdss. Figure measurements are necessary. The HVU not only forces a maximum voltage of lOOOV, but measures current with 2pA resolution. For breakdown voltage measurements, the HVU has the quasipulse measurement mode’ for precision measurements by minimizing the duration of the breakdown condition. 4. Measurement program 1 Quasi-pulse measurement mode The measurement sequence of this mode follows: i) Force current specified by the user as current compliance. ii) Monitor the voltage and calculate the voltage slew rate. iii) When the Device Under Test (DUT) is in the breakdown condition, the current starts flowing rapidly and the voltage slew rate becomes flat. The unit detects this point, waits a userspecified delay time, and measures the output voltage. iv) After the measurement, the output voltage is rapidly returned to the start voltage. 4 This example shows how to programmatically measure the Icbo parameter of a power bipolar transistor by using an external relay. The example uses the Voltage Source (VS) of a Voltage SourceNoltage Meter Unit (VSNMU) to control the external relay. Before the measurement, make a measurement module as shown 2.1.2. Enhancing Automatic Measurements by External Relay Control You can open or short the output of the SMU by using the following methods: OPEN Make the output current 0 A in current force mode. SHORT Make the output voltage 0 V in voltage force mode. For example, use these methods to open the base when you measure the BVceo of a bipolar transistor or to short the gate (grounded) when you measure the BVdss of a MOSFET, without ever having to remove the SMU from the base or the gate. When you measure certain parameters of a bipolar transistor or a MOSFET, the emitter of the bipolar transistor or the source of the MOSFET are usually connected to the ground unit (GNDU) and not to the SMU. Conversely, the connection between the GNDU and the device needs to be open when measuring other parameters, such as Icbo of a bipolar transistor. Opening and shorting the SMU make the configurations trouble-free. $ in Figure 5 by fixing the relay to the universal module (P/N 16088-60010). The default condition for the external relay is closed By forcing a specified voltage to the relay from VS, the external relay is opened, and the connection between the GNDU and the emitter is opened. Figure 6 shows the measurement circuit, Figure 7 shows the measurement results, 7 HVU Figure lcbo = 1.7128E-7 6. Measurement circuit (A) VS 0 ~ i User 1 Caps Idle GNDU Figure 5. Measurement 1 module Figure 7. Measurement result 5 and Figure 8 shows the program. An external relay used with a module selector (as shown in Figure 9) is an easy way to make even more versatile and automatic measurements. For instance, the connection to the GNDU and the transistor emitter can be opened to extract the Icbo parameter of a transistor. 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 OPTION ASSIGN Hpsmu=2 Hvu=7 vsl=18 vc=400 BASE 1 @Hp4142 TO 723 ! vc = 4oov ! IC camp = 1omA Iccomp=.Ol ! relay disconnect V-off=12 ! "CN";H~~,H~~~U,VS~ OUTPUT @Hp4142; OUTPUT @Hp4142;"FMT";5 OUTPUT @Hp4142;"DV";Vsl,O,V off OUTPUT @Hp4142;"DV0~;Hpsmu,0~0,1ccomp OUTPUT @Hp4142;"DV~~;Hvu,O,Vc,ICCOrnp OUTPUT @Hp4142;"MN";1,H~~ OUTPUT @Hp4142;"XE" ENTER @Hp4142 USING "#,3A,12D,X";A$,Icbo OUTPUT @Hp4142;"CL" PRINT "Icbo = ";Icbo;"(A)" END voltage 20-90 Initialization. 110 Set the output switches of measurement modules to ON. 120 Specify format of the measurement data. 130 Open the relay OPEN by forcing 12 V to the relay from VS. 140 Ground the base. 160-200 Perform the measurement and display the results. -Frgure 8. Measurement program Figure 9. Auto extraction of parameters external relay and module selector with 6 2.2. Extending the Measurement Range Since the HP 4142B can programmatically connect an HPSMU, HCU, or HVU to a device pin by using the module selector, you can make very wide-ranged measurements, as shown in the white area of Figure 10. In addition, you can use two HPSMUs, HCUs, or HVUs to extend the measurement range into the range indicated by the diagonal lines in Figure 10. In this section, the measurement examples for devices that work in the extended voltage/current area of Figure 10 are shown. I ^^ m Fss$ Standard Conflguratlon MP 41420A. 414ZlB,4i422A. Expandable (Depend on the configuration 3 za, *l : &her, "s,"g 41423N of plug-in units) cnly 2 HVUs 5 0 IOOm i 10m 1 20f Lb 4ou 10 100 200 Voltage 1K ZK N) Figure 10. Current by the HP 4142B. and voltage range covered 2.2.1. 2000V Measurement One HVU can make breakdown tests of up to 1OOOV. You can increase the maximum voltage to 2000 V by using two HVUs in differential mode. The extended range is shown by diagonal lines in Figure 11. This is very useful for breakdown voltage measurements or current leakage measurements of 8OOl9OOV power transistors and SSRs (Solid State relays), both of which are used for switching power lines. This example shows how to measure breakdown voltage of an 800 V power transistor. The measurement result, measurement circuit, and measurement program are shown in Figures 12-14. One HVU is connected to the collector and the other is connected to the emitter. First, - 1OOOV (BVl) is applied to the emitter. Since the HVU is unipolar, you need to change the polarity of the HVU to negative t 1 Standard conflguratlon (HP 41420A. 414218. 41422A. 414238) ya: Expandable (Depend on the confIguratIon * (iOV.2ON * (ZOV. 1OA i 1 /(14V. 1 ~ of plug-In units) I i6A) t .(20V.l4A) I * (4OV. 700mA) . (BOV, 350mA) * (iOOV, 250mA) Voltage ii1 : &tier, using crly 2 HVUs N) Figure 11. Expanding range with two HVUs in advance. Second, by using the break down command, a quasipulse is applied by the HVU connected to the collector. Then the current in series. and voltage the voltage at the collector (BV2) is measured. By subtracting BVl from BV2, you can get the actual breakdown voltage. a 2.2.2. lOAl20V Measurement One HCU can output or measure up to 10AllOV. You can extend this range to lOAl2OV by using two HCUs. The extended range is shown by diagonal lines in Figure 15. The extended measurement range makes it possible to evaluate devices that drive dc motors for cars. This example shows how to measure Id-Vg characteristics by sweeping Vd from OV to 20V. The measurement circuit, measurement result, and measurement program are shown in Figures 16-18. One HVU is connected to the drain and the other is connected to the source, and an SMU is connected to gate. The measurement mode is set to dual pulse sweep measurement mode. The HCU is designed to output only pulse, so to perform a OV to 20V sweep measurement, the sweep measurement is made two times: OV to 1OV and IOV to 20V. In the first measurement, the HCU connected to the source forces OV while the HCU connected to the drain forces sweep outputs varying from OV to 1OV. The Id parameter is measured in every step. In the second measurement, each voltage value that was applied to the gate in the first measurement ‘i HCU A HCU A GNDU Figure 16. Measurement circuit minus ten volts is applied to the gate. The HCU connected to the drain forces sweep outputs varying from OV to 1OV. This is equivalent to sweeping from 1OV to 20V to the device. By sweeping Vd from OV to 2OV, these two measurements give the IdVd measurement as shown in Figure 17. i Standard configuration (HP 414ZOA. 414218. 41422A. 41423A) y/A Expandable (Depend on the conflguratlon * uov, 2ON (ZOV. ION of plug-l? units) ? (4OV. 7OOmAi . 10m ZOf 10 100 200 Voltage (6OOV. 20mA) r L (IOOOV. 12mAi : r(iZOOV, lOmA) . / 1K :\ (2OOOV. 6mA) i ZK I N) Figure 15. Expanding the current and measurement range with two HCUs in series. 41 10 2.2.3. 20AllOV Measurement The previous example shows a lOAl2OV measurement by two HCUs in series. By using two HCUs in parallel, you can extend the measurement range up to 20A/lOV. The measurement range extended by this configuration is shown by diagonal lines in Figure 19. This example shows how to measure Ic-Vc characteristics of the power bipolar transistor. The Ic parameter can easily exceed 10A. The measurement circuit, measurement result, and measurement program are show in Figures 20-22. The HCUs are connected in parallel between the collector and emitter as shown in Figure 20. The measurement mode is set to 2 channel pulsed sweep mode to synchronize the HCUs. The two HCUs are current sources that sweep current values from OA to 10A. Current from the two HCUs flow into the bipolar transistor, which is equivalent to a sweep from OA to 20A. By measuring the voltage at the top of either HCU, you can get Ic-Vc characteristics with 20A. s$$ Expandable (Depend on the configuration 20. Measurement circuit of plug-In units) 4 9 (ZOOV. 125mN * (4OOV. 50mN (6OOV. 20mA) 1; 10m i ZOf T 1, 4ou , 10 I 100 200 Voltale 1K 2K (jli Figure 19. Expanding the current and measurement range with two HCUs in parallel. lc-vc -4 6 I@ (xEE1 vc (VI GNDU Figure Standard conflguratlon (HP 41420A. 414218. 414228, 41423A) (4OV. 700mA) . (BOV, 350mA) ’ (IOOV. 250mA) 2 SMU 1 Fieure 21. Measurement result 12 2.2.4. High Power Measurement (250mA x lOOV, 125mA x 200V) By connecting two HPSMUs in series or in parallel, you can make very high power measurements. This is effective for measuring the channel-on breakdown voltage of EL (Electra Luminescence) and PDP (Plasma Display Panel). The measurement range extended by this configuration is shown by diagonal lines in Figure 23. This example shows how to measure Id-Vd characteristics in the high power measurement range by connecting two HCUs in parallel. The measurement circuit, measurement results, and measurement program are shown in Figure 24-26. The white area inside the broken lines in Figure 25 shows the measurement range that can be covered with one HCU. Using two HPSMUs lets you extend the measurement range into the area indicated by diagonal lines. 0 HPSMU x 1 ;///: riPSMli x 2 IMOb’. ‘OOmkl (1OOV. 250mA) 1 1 100 0 ////,? ,,,,,,,,,y;{V 125mA) Figure 23. Expanding the current and measurement range with two HPSMIJs pXalld. r II0I!!!! V GNDU 1 HPSMU V 1 HPSMU Figure 24. Measurement circuit Id-Vd 01 ““““““‘A” B 1 I0 20 Vd Figure 25. Measurement result 36 (VI ” 40 (xE0) ~ in