All Semicoa products are designed to meet radiation hardness requirements. Our line of Rad Hard devices are specifically designed to tolerate higher levels of radiation and are guaranteed at a high level of statistical performance (0.99/90%, KTL Statistics for each parameter and parameter delta), above and beyond what the industry requires for RHA qualification.
We have the in-house capability to perform most environmental and life tests required by MIL-PRF-19500 for JAN through JANS level transistors, including additional tests specific to customer requirements. All areas are ESD compliant.
Rad Hard Program
Semicoa has the broadest Radiation Hardness Assured (RHA) Bipolar Transistor product offering on the MIL-PRF-19500 Qualified Part List (QPL). Semicoa currently has 42 unique 2N numbers available in various levels of RHA and the majority are qualified up to 300 Krad or JANSF level.Semicoa has the most stringent Radiation Hardness Assurance Program in the semiconductor market and has set the benchmark for qualifying RHA devices. All RHA devices are qualified with a larger samples size than what is required by MIL-PRF-19500; most of our RHA devices are qualified with a sample size of 11 per wafer. The maximum sample size required by MIL-PRF-19500 is 4 per wafer. Only the very largest die, those that come from wafers where we yield less than 500 die per wafer, at tested with a smaller samples size, of 5 per wafer. MIL-PRF-19500 only requires a samples size of 1 for these wafers. Semicoa uses the Group D end points as acceptance criteria and develops a radiation delta acceptance criteria by taking the Group D end point and subtracting the Group A endpoint to calculate a delta parameter acceptance criteria. All of these acceptance criteria must be met when we test a wafer for the device to be classified as RHA Product. Furthermore, statistics are used for deciding if the wafer meets the radiation requirement by calculating the 0.99/90% tails of the distribution based on the small sample tested and comparing those tails to the upper of lower acceptance criteria for the parameter of interest. All parameters and parameter deltas must meet their acceptance criteria at the 0.99/90% level in order for a wafer to be considered RHA by Semicoa. This approach was developed based on our customer’s program requirements and the methodology required for characterizing parts for usage on most military and space programs. Semicoa eliminates the need to re-test RHA devices in order to demonstrate program compliance.
Special Radiation Characterization
Semicoa can perform almost any type of special radiation characterization or qualification needed for any of our products. Semicoa specializes in taking on customer radiation requires in Selected Item Drawings and providing a fully compliant part, thus eliminating the lot jeopardy. Semicoa has experience in a wide variety of radiation effects testing like: high dose rate total dose, low dose rate total dose, displacement damage, nuclear gamma dose rate testing in narrow and wide pulse, and single event effects testing.
Rad Hard By Design Bipolar Transistor Technology
Semicoa has developed a Rad Hard By Design Bipolar Transistor Technology that can be applied to either NPN or PNP devices to improve the total dose hardness of the device to a minimum of 300 Krad with excellent wafer-to-wafer and lot-to-lot uniformity. This process allows Semicoa to take any of its transistors and improve the total dose performance while maintaining the same die geometry and junction profile. The RHBD die are form, fit, and function equivalent to the standard device and are qualified to the same MIL-PRF-19500 slash sheet. The RHBD version of the device will be available for the next higher radiation level that the standard devices are qualified to on the QPL. For example the standard version of the 2N2222A is only available up to JANSR (100 Krad), the RHBD version of the 2N2222A will be available starting at the JANSF (300 Krad) version. Therefore, the RHBD devices will have a unique part number to differentiate them from the standard products. Some preliminary low dose rate total dose testing has been performed on the RHBD Technology and preliminary results indicate that it is almost immune to the environment up to 100 Krad. Testing has been performed by NASA/Goddard under their Ultra ELDRS Program and they tested the RHBD version of the 2N2222A. No low dose rate enhancement is observed up to 100 Krad using a dose rate of 10 mrad/s with parts biased and unbiased during exposure. Testing is also being performed at 1 mrad/s with no enhancement seen at 40 Krad and similar results have been observed using 0.5 mrad/s up to 20 Krad.
Rad Hard Bipolar Transistor Technology at JANTXV Quality Level
Semicoa has introduced all of their Rad Hard Bipolar Transistors at JANTXV quality level plus the guarantee of radiation hardness. Due to the enhanced methodology used by Semicoa to qualify RHA products, all RHA devices qualified for JANS are also qualified for JANTXV in accordance with MIL-PRF-19500. Currently Semicoa has 16 unique devices listed on the QPL at this quality level plus radiation hardness and plans to add the remaining 26 devices by the end of the year to the QPL. These devices are qualified using the Semicoa Enhanced Acceptance Criteria so each device will meet the Group D endpoints and the parameter deltas using 0.99/90% statistics.
Surface Mount, Low Dose Rate (LDR) Total Dose Qualified Bipolar Transistors
Semicoa is now offering Surface Mount, Low Dose Rate (LDR) Total Dose qualified Bipolar Transistors tested at 10 mrad/s and characterized for the effects of displacement damage. Each wafer of LDR product will be radiation lot acceptance tested using a sample size of 22 irradiated devices with half biased during irradiation the other half unbiased. Parts will also be annealed at room temperature and high temperature (100°C) following the exposures. The devices must meet the Group D, Subgroup 2 endpoints and the parameter deltas (Group D minus Group A), using 0.99/90% statistics in order to be qualified as LDR Product. The device technology will be characterized for the effect of displacement damage using neutrons up to a level of 2E12 n/cm2 and the data will be presented in the product specification. Each device will be offered in three different total dose levels of 30, 50, and 100 Krad and the devices will be marked with a Semicoa unique part number to specify this level. An example of the part marking will be SCA2N2222AUBX, where X is the designation for the radiation hardness level and will be identical to the Rad Hard letters defined in MIL-PRF-19500, Table E-II. Therefore, X can be P for 30 Krad, L for 50 Krad, and R for 100 Krad.