Application Note 1895 Total Dose Testing of the ISL71590SEH Radiation Hardened Temperature Sensor Introduction Part Description This report documents the results of low and high dose rate total dose testing and subsequent anneals of the ISL71590SEH radiation hardened temperature sensor. The tests were conducted to provide an assessment of the total dose hardness of the part and to provide an estimate of dose rate sensitivity. Parts were irradiated under bias and with all pins grounded at low and high dose rate. The ISL71590SEH is acceptance tested on a wafer-by-wafer basis to 300krad(Si) at high dose rate (50 to 300rad(Si)/s) and to 50krad(Si) at low dose rate (0.01rad(Si)/s). The ISL71590SEH is a radiation hardened two terminal temperature transducer. It has a high impedance current output that allows it to be insensitive to voltage drops across long lines. With a supply voltage of between 4V and 36V applied to the input pin, the device acts as a constant current generator with a scale factor of 1μA/K. The ISL71590SEH is specified across the -55°C to +125°C temperature range and can operate across the -55°C to +150°C temperature range without the need of additional circuitry. Downpoints to date for the low dose rate tests were zero, 10, 30 and 50krad(Si); the test will be extended to 150krad(Si), with a downpoint at 100krad(Si). Downpoints to date for the low dose rate tests were zero, 10, 30, 50, 114 and 150krad(Si). Downpoints for the high dose rate tests were 0, 30, 50, 100, 300 and 450krad(Si). All irradiations and anneals are complete. Reference Documents • MIL-STD-883 test method 1019 • ISL71590SEH datasheet • Standard Microcircuit Drawing (SMD) 5962-13215 With power requirements as low as 1.5mW (5V at +25°C), the part is an ideal choice for payload and booster temperature sensing as any well-insulated twisted pair cable can be used for proper operation. The ISL71590SEH can be used in a wide range of applications including temperature compensation networks, laser diode temperature compensation, sensor bias and linearization functions and Proportional To Absolute Temperature (PTAT) biasing. The high output impedance (>10MΩ) leaves plenty of room for variations in the power supply voltage. The part is electrically durable as it can withstand an absolute maximum forward voltage of 40V outside of the heavy ion environment (with a 37V absolute maximum in-beam rating) and a reverse voltage of -40V. The ISL71590SEH is available in a 2 lead hermetically sealed flatpack. Key Features • Minimal accuracy shift over total dose rate irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1.5K to +0.5K • Linear output current. . . . . . . . . . . . . . . . . . . . . . . . . . 1.0μA/K • Wide operating power supply range . . . . . . . . . . . . 4V to 31V • Low power consumption . . . . . . . . . . . . . 1.5mW at 5V supply • Operating temperature range. . . . . . . . . . . .-55°C to +125°C • SEL/SEB threshold LET . . . . . . . . . . . . . . . 86.4MeV•cm2/mg • Total dose tolerance, high dose rate . . . . . . . . . . 300krad(Si) • Total dose tolerance, low dose rate . . . . . . . . . . . . .50krad(Si) • QML qualified per MIL-PRF-38535 • Produced in conformance with Standard Microcircuit Drawing (SMD) 5962-13215 September 24, 2015 AN1895.1 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2013, 2015. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. Application Note 1895 Test Description Characterization Equipment and Procedures Irradiation Facilities High dose rate testing was performed at 69.7rad(Si)/s using a Gammacell 220 60Co irradiator located in the Palm Bay, Florida Intersil facility. Low dose rate testing was performed at 0.01rad(Si)/s using the Intersil Palm Bay Hopewell Designs N40 panoramic 60Co irradiator. Annealing was performed under the Figure 1 bias configuration at +100°C for 168 hours using a small temperature chamber. Test Fixturing Figure 1 shows the configuration used for biased irradiation at both high and low dose rate. V1 = 5V ±5% 1 2 1 GND 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 U1 NOTE: This socket/carrier holds ten individual devices with the carrier positions labeled 1 through 10. U2 U3 All electrical testing was performed outside the irradiator using the production Automated Test Equipment (ATE) with datalogging at each downpoint. Downpoint electrical testing was performed at room temperature. Due to the precision nature of the part, all electrical characterisation is performed using production ATE and an advanced constant-temperature liquid bath facility. Experimental Matrix Total dose irradiation proceeded in accordance with the guidelines of MIL-STD-883 Test Method 1019.7. The experimental matrix consisted of five samples irradiated at low dose rate under bias, five samples irradiated at low dose rate with all pins grounded, five samples irradiated at high dose rate under bias and five samples irradiated at high dose rate with all pins grounded. Samples of the ISL71590SEH were drawn from preproduction wafer lot X0A8P and were packaged in the hermetic 2-pin solder-sealed production flatpack (K2.A) package. Samples were processed through the standard burn-in cycle before irradiation, as required by MIL-STD-883. Downpoints Downpoints for the low dose rate tests were 0, 10, 30, 50, 114 and 150krad(Si). Downpoints for the high dose rate tests were 0, 30, 50, 100, 300 and 450krad(Si). All irradiations were followed by a high temperature anneal at +100°C under bias. U4 U5 U6 U7 U8 U9 U10 FIGURE 1. IRRADIATION BIAS CONFIGURATION FOR THE ISL71590SEH Submit Document Feedback 2 AN1895.1 September 24, 2015 Application Note 1895 Test Results Attributes Data TABLE 1. ISL71590SEH TOTAL DOSE TEST ATTRIBUTES DATA PART DOSE RATE, RAD(SI)/S BIAS SAMPLE SIZE 0.01 Figure 1 5 ISL71590SEH ISL71590SEH 0.01 ISL71590SEH 69.7 ISL71590SEH 69.7 Grounded Figure 1 Grounded 5 5 5 PASS (Note 1) FAIL Pre-irradiation 5 0- 10krad(Si) 5 0 30krad(Si) 5 0 50krad(Si) 5 0 114krad(Si) 1 4 150krad(Si) 0 5 Anneal 1 4 Pre-irradiation 5 -- 10krad(Si) 5 0 30krad(Si) 5 0 50krad(Si) 5 0 114krad(Si) 0 5 150krad(Si) 0 5 Anneal 2 3 Pre-irradiation 5 30krad(Si) 5 0 50krad(Si) 5 0 100krad(Si) 5 0 300krad(Si) 5 0 450krad(Si) 5 0 Anneal 5 0 Pre-irradiation 5 30krad(Si) 5 0 50krad(Si) 5 0 100krad(Si) 5 0 300krad(Si) 5 0 450krad(Si) 5 0 Anneal 5 0 DOWNPOINT NOTE: 1. ‘Pass’ indicates a sample that passes all post-irradiation SMD limits. Submit Document Feedback 3 AN1895.1 September 24, 2015 Application Note 1895 Variables Data The plots in Figures 2 through 7 show data at all downpoints. We plotted the average, minimum and maximum of the total dose response for each parameter at low and high dose rate. For clarity in interpreting the temperature error data, Figure 2 shows the combined low and high dose rate response, Figure 3 shows the low dose rate response only and Figure 4 shows the high dose rate response only. 1.0 LDR AND HDR SPEC LIMIT TEMPERATURE ERROR (KELVIN) 0.5 0 ANNEAL 2 -0.5 -1.0 ANNEAL 1 -1.5 SPEC LIMIT -2.0 -2.5 LDR GND AVG LDR GND MIN LDR GND MAX LDR BIAS AVG LDR BIAS MIN LDR BIAS MAX HDR GND AVG HDR GND MIN HDR GND MAX HDR BIAS AVG HDR BIAS MIN HDR BIAS MAX -3.0 -3.5 0 100 200 300 400 500 TOTAL DOSE (krad(Si)) FIGURE 2. ISL71590SEH temperature error in Kelvin as a function of total dose irradiation at low and at high dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The low dose rate was 0.01rad(Si)/s and the high dose rate was 69.7rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 1’ was performed after 150krad(Si) at low dose rate while ‘Anneal 2’ was performed after 450krad(Si) at high dose rate. The sample size for all cells was 5. The post-irradiation SMD specification limits are -1.5K to +0.5K. 1.0 LDR ONLY TEMPERATURE ERROR (KELVIN) 0.5 SPEC LIMIT 0 -0.5 -1.0 -1.5 ANNEAL 1 -2.0 LDR GND AVG LDR GND MIN LDR GND MAX LDR BIAS AVG LDR BIAS MIN LDR BIAS MAX SPEC LIMIT -2.5 -3.0 -3.5 0 100 200 300 400 500 TOTAL DOSE (krad(Si)) FIGURE 3. ISL71590SEH temperature error in Kelvin as a function of total dose irradiation at low dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The dose rate was 0.01rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 1’ was performed after 150krad(Si) at low dose rate. The sample size for all cells was 5. The post-irradiation SMD specification limits are -1.5K to +0.5K. Submit Document Feedback 4 AN1895.1 September 24, 2015 Application Note 1895 1.0 HDR ONLY SPEC LIMIT TEMPERATURE ERROR (KELVIN) 0.5 0 HDR GND AVG HDR GND MIN HDR GND MAX HDR BIAS AVG HDR BIAS MIN HDR BIAS MAX -0.5 ANNEAL 2 -1.0 -1.5 SPEC LIMIT -2 0 100 200 300 400 500 TOTAL DOSE (krad(Si)) FIGURE 4. ISL71590SEH temperature error in Kelvin as a function of total dose irradiation at high dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The dose rate was 69.7rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 2’ was performed after 450krad(Si) at high dose rate. The sample size for all cells was 5. The post-irradiation SMD specification limits are -1.5K to +0.5K. 0.6 POWER SUPPLY REJECTION, 4V (µA/V) SPEC LIMIT 0.4 0.2 ANNEAL 1 LDR GND AVG LDR GND MIN LDR GND MAX LDR BIAS AVG LDR BIAS MIN LDR BIAS MAX HDR GND AVG HDR GND MIN HDR GND MAX HDR BIAS AVG HDR BIAS MIN HDR BIAS MAX 0 ANNEAL 2 -0.2 -0.4 SPEC LIMIT -0.6 0 100 200 300 400 500 TOTAL DOSE (krad(Si)) FIGURE 5. ISL71590SEH power supply rejection at 4V, in µA/V, as a function of total dose irradiation at low and at high dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The low dose rate was 0.01rad(Si)/s and the high dose rate was 69.7rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 1’ was performed after 150krad(Si) at low dose rate while ‘Anneal 2’ was performed after 450krad(Si) at high dose rate. The sample size for all cells was 5. The post-irradiation SMD specification limits are -0.5µA/V to +0.5µA/V. Submit Document Feedback 5 AN1895.1 September 24, 2015 Application Note 1895 0.25 SPEC LIMIT POWER SUPPLY REJECTION, 15V (µA/V) 0.20 0.15 0.10 ANNEAL 1 ANNEAL 2 0.05 0 -0.05 -0.10 -0.15 LDR GND AVG LDR GND MIN LDR GND MAX LDR BIAS AVG LDR BIAS MIN LDR BIAS MAX HDR GND AVG HDR GND MIN HDR GND MAX HDR BIAS AVG HDR BIAS MIN HDR BIAS MAX SPEC LIMIT -0.20 -0.25 0 100 200 300 400 500 TOTAL DOSE (krad(Si)) FIGURE 6. ISL71590SEH power supply rejection at 15V, in µA/V, as a function of total dose irradiation at low and at high dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The low dose rate was 0.01rad(Si)/s and the high dose rate was 69.7rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 1’ was performed after 150krad(Si) at low dose rate while ‘Anneal 2’ was performed after 450krad(Si) at high dose rate. Sample size for all cells was 5. The post-irradiation SMD specification limits are -0.2µA/V to +0.2µA/V. POWER SUPPLY REJECTION, 31V (µA/V) 0.15 SPEC LIMIT 0.10 ANNEAL 2 0.05 0 ANNEAL 1 -0.05 SPEC LIMIT -0.10 -0.15 0 100 200 300 400 LDR GND AVG LDR GND MIN LDR GND MAX LDR BIAS AVG LDR BIAS MIN LDR BIAS MAX HDR GND AVG HDR GND MIN HDR GND MAX HDR BIAS AVG HDR BIAS MIN HDR BIAS MAX 500 TOTAL DOSE (krad(Si)) FIGURE 7. ISL71590SEH power supply rejection at 31V, in µA/V, as a function of total dose irradiation at low and at high dose rate for the biased (per Figure 1) and unbiased (all pins grounded) cases. The low dose rate was 0.01rad(Si)/s and the high dose rate was 69.7rad(Si)/s. The irradiations were followed by a +100°C 168 hour biased anneal; ‘Anneal 1’ was performed after 150krad(Si) at low dose rate while ‘Anneal 2’ was performed after 450krad(Si) at high dose rate. Sample size for all cells was 5. The post-irradiation SMD specification limits are -0.1µA/V to +0.1µA/V. Submit Document Feedback 6 AN1895.1 September 24, 2015 Application Note 1895 Discussion and Conclusion We report the results of a characterisation total dose test of the ISL71590SEH integrated temperature sensor. All irradiations were followed by a high temperature anneal at +100°C under bias. All electrical measurements were performed at room temperature and were performed before irradiation, after each irradiation step and after each annealing period. This is a simple part with one key performance parameter, the temperature error, but that simplicity does not necessarily translate into easy electrical testing. Careful liquid-bath testing using Fluorocarbon fluid is required for repeatable and accurate data (and for adequate production testing as well, incidentally) and we used four control units at each test operation to insure repeatable data. Figures 2 through 7 show the total dose and anneal response of the part’s parameters. In Figure 2 we plot both the low and high dose rate response on the same set of axes, while Figures 3 and 4 show the low dose rate and high dose rate responses separately. The temperature error showed a very gradual change (Figures 2 and 4) from the pre-irradiation value of near zero to -0.5K after 450krad(Si) with no anneal response. The low dose rate irradiation produced more pronounced shifts (Figures 2 and 3), with the samples within the -1.5K to +0.5K SMD limits after 50krad(Si) but out of specification on the negative side after the 114krad(Si) and 150krad(Si) downpoints. We observed a strong anneal response back to approximately the lower -1.5K limit, see Figures 2 and 3. Interestingly, we observed no bias sensitivity at all for either dose rate. The power supply rejection is the only other measured parameter and was found to be stable at 4V, 15V and 31V supply voltage, although the data for the 114krad(Si) low dose rate downpoint is highly suspect, especially for the 31V case (see Figure 7). The parameter remained well within the respective SMD limits at all downpoints. We conclude that the temperature error remained within the -1.5K to +0.5K SMD post-irradiation specification limits after the 50krad(Si) at low dose rate or 300krad(Si) at high dose rate specified in that drawing, but the part must be considered low dose rate sensitive based on the ‘delta parameter’ diagnostic algorithm outlined in MIL-STD-888 test method 1019 or based simply on inspection of Figure 2. As noted before, the ISL71590SEH is acceptance tested on a wafer-by-wafer basis at both low and high dose rate. No differences in total dose response between biased and grounded irradiation were noted at either dose rate, and the part is hence not considered bias sensitive. Interestingly, high temperature biased annealing following low dose rate irradiation produced a strong anneal signature, while performing the same step on high dose rate samples produced no response at all. Appendices TABLE 2. REPORTED PARAMETERS AND THEIR POST-IRRADIATION LIMITS FIGURE PARAMETER LIMIT LOW LIMIT HIGH UNITS NOTES 2 Temperature error, high and low dose rate -1.5 +0.5 K 3 Temperature error, low dose rate -1.5 +0.5 K 4 Temperature error, high dose rate -1.5 +0.5 K 5 Power supply rejection ratio -0.5 +0.5 µA/V 4V supply 6 Power supply rejection ratio -0.2 +0.2 µA/V 15V supply 7 Power supply rejection ratio -0.1 +0.1 µA/V 31V supply Revision History The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to the web to make sure that you have the latest revision. DATE REVISION CHANGE September 2, 2015 AN1895.1 Final report - all irradiations and anneals are complete. November 1, 2013 AN1895.0 Initial report. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that the document is current before proceeding. For information regarding Intersil Corporation and its products, see www.intersil.com Submit Document Feedback 7 AN1895.1 September 24, 2015