Experiment 4 MOS Device Characterization1.0 Objective2.0 Prelab1. Review lecture/discussion notes relating to MOSFET physics/regions of operation.2. Prepare a SPICE deck for the circuit in Fig. 1. Let VDS range from 0 - 5 V in 0.1V increments and let VGS range from 0 - 5V in 1V increments. Print a plot of ID vs. VDS with VGS as a parameter. Using this plot, explain how one would obtain...FIGURE 1. Circuit for SPICE simulation as described in Prelab procedure 2.3. Prepare a SPICE deck for the circuit in Fig. 2. Print a plot of ID vs. VGS. Let VGS range from 0 to 5V. Using this plot, explain how one would obtain the parameters VTO and Kn = mnCox. Use the same SPICE parameters as procedure 2.FIGURE 2. Circuit for SPICE simulation as described in prelab procedure 3.3.0 Procedure1. Check out 3 banana cables and a Lab Chip 1 chip from your lab TA.2. Place chip Lab Chip 1 into the parameter analyzer test fixture or Lab Chip socket on your breadboard. If using the breadboard, DO NOT place your Lab Chip in any other place besides in the socket at the center of the board. The pinouts for ...FIGURE 3. 4155 Test Fixture showing SMU1 being connected to pin 2 of a 28pin chip.FIGURE 4. Circuit to gather data for ID vs. VDS plot. Note SMUs in dashed boxes.3. Using the Metrics program (see Lab 3), step the gate voltage from 0 to 5V and sweep from 0 to 5 V to obtain a drain current versus drain-source voltage plot similar to that displayed in Figure 5.4. Determine ln from the plots obtained in part 3 above (see appendix for assistance on this matter).5. Comment on the shape of the graphs obtained in part 3. In particular, how does VDS(SAT) compare with theory? How does ID(SAT) compare with theory? Your compar isons should be quantitative.6. Obtain print outs of your data.FIGURE 5. Sample ID vs. VDS characteristic of NMOSFIGURE 6. Sample ID vs. VDS characteristic showing a best fit line to find ln3.1 Finding VTOn and Kn in the Triode Region.1. Using the Metrics program, configure the SMUs to provide a setup similar to that displayed in Figure 7. More specifically, make the drain-source voltage a constant 50mV and sweep the gate-source voltage from 0 to 5V to obtain a plot of ID vs. VGS.2. The MOSFET is in the triode region for VGS > VTOn + 50 mV; write the equation for ID that corresponds to this region of operation.FIGURE 7. Circuit to gather data for ID vs. VGS plot. Note SMUs in dashed boxes.3. From your plot of ID vs. VGS in the triode region, find the best-fit line and estimate both VTn and the Kn parameter. Use the W and L values from the prelab in your cal culations.4. Obtain print outs of your data.3.2 Finding VTOn and Kn in the Saturation Region.1. Using the Metrics program, configure the SMUs to provide a setup similar to that displayed in Figure 8. More specifically, make the drain-source voltage a constant 5V and sweep the gate-source voltage from 0 to 5V to obtain a plot of ID vs. VGS.2. The MOSFET is in the saturation region for VGS < VTOn + 5 V; write the equation for ID that corresponds to this region of operation.3. Find the best fit line for the plot of ID1/2 vs. VGS in the saturation region, as shown in Fig. 10. Use the slope and intercept of the best-fit line to estimate both VTn and the Kn parameter.4. Obtain print outs of your data.FIGURE 8. Circuit to gather data for (ID)1/2 vs. VGS plot. Note SMUs in dashed boxes.FIGURE 9. Sample ID vs. VGS characteristic of NMOSFIGURE 10. Sample (ID)1/2 vs. VGS characteristic showing a best fit line to find VTo and Kn.3.3 Comparison with SPICE1. Fill in the value of VTO, Kn, and ln in the data sheet in the appendix. You will need to refer to these values in future labs.2. The values you extracted will be used in SPICE to model the NMOS. Using the SPICE decks that you have done for prelab, replace the values of VTo, Kn, and ln with the ones you just found. (note that Kn is defined as Kp in SPICE)3. Obtain plots of ID vs. VDS and ID vs. VGS as you did in prelab.4. Compare the experimental plots with the plots you generated in SPICE. How do the values of ID(SAT) compare for a given VDS(SAT)? Note that the Level 1 SPICE model is not adequate for accurate modeling of devices with channel lengths shorte...4.0 Optional Experiments (Extra Credit)4.1 PMOS Characterization Repeat the above, but this time for a PMOS transistor. You will need to check out a Lab Chip 2 chip from your lab TA.5.0 Appendix5.1 Data Sheet5.2 MOSFET Parameter Extraction (Saturation Region)FIGURE 11. Square root of ID vs. VDS for NMOS in saturation (not assigned)5.2.1 VTo Extraction5.2.2 g Extraction5.2.3 mn Extraction5.2.4 Channel Length ModulationFIGURE 12. ID vs. VDS plot for MOSFET1 of 11Experiment 4 MOS Device CharacterizationW. T. Yeung and R. T. HoweUC Berkeley EE 105Fall 20041.0 ObjectiveIn this experiment, you will find the device parameters for an n-channel MOSFET. From the parameters, you will reproduce its I-V characteristics and compare them to SPICE. The characteristics will be compared to the SPICE level 1 model. We will also compare your data with data from the HP 4155 analyzer. The key concepts you should learn in this lab are:• determining which region of operation the MOSFET is in depending on the values of VGS and VDS,• application of correct equations for ID depending on the region of operation,• extraction of basic SPICE parameters from experimental measurements2.0 Prelab1. Review lecture/discussion notes relating to MOSFET physics/regions of operation.2. Prepare a SPICE deck for the circuit in Fig. 1. Let VDS range from 0 - 5 V in 0.1V increments and let VGS range from 0 - 5V in 1V increments. Print a plot of ID vs. VDS with VGS as a parameter. Using this plot, explain how one would obtain the parame-ters VTOn, Kn= µnCox and λn. Use the following SPICE parameters for getting started: (note SPICE uses Kp for Kn.)• VTOn =1 V• Kp=100 (µA/V2)• λn = 0.05 V-1Procedure2 of 11 Experiment 4 MOS Device CharacterizationFIGURE 1. Circuit for SPICE simulation as described in Prelab procedure 2.3.Prepare a SPICE deck for the circuit in Fig. 2. Print a plot of ID vs. VGS. Let VGS range from 0 to 5V. Using this plot, explain how one would obtain the parameters VTO and Kn= µnCox. Use the same SPICE parameters as procedure 2.FIGURE 2. Circuit for SPICE simulation as described in prelab procedure 3.3.0 Procedure1. Check out 3 banana cables and a Lab Chip 1 chip from your lab TA.2. Place chip Lab Chip 1 into the parameter analyzer test fixture or Lab Chip
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