Total Ionizing Dose Effects Research Articles

9‐1: Evaluation of X‐ray Resistance of Submicron‐Size c‐Axis Aligned Crystalline‐Oxide Semiconductor

We have investigated the total ionizing dose effect by X‐rays, which is a degradation mode of a single transistor, to find the radiation resistance of oxide semiconductor large scale integrated circuit. At 3000 Gy corresponding to the absorbed dose for 30 years in a space environment, or more specifically, on a geostationary orbit, an oxide semiconductor field‐effect transistor showed a negative drift in threshold voltage of less than 300m V and substantially no degradation in subthreshold slope and mobility. After 60 hours from the irradiation, approximately 40% of the threshold voltage variation was recovered.

A Comprehensive Study of Total Ionizing Dose Effect on the Electrical Performance of the GaN MIS-HEMT

In this work, the effect of Total Ionizing Dose (TID) on the performance of GaN on Si MIS-HEMT power devices with in-situ SiN cap layer is investigated. 13 samples were exposed to different accumulated dose (100 krad and 400 krad) of Co <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{60}~\gamma $ </tex-math></inline-formula> -ray irradiation with two bias conditions (grounded and stressed). The characteristics of the devices after irradiation experiment were evaluated by measuring V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</sub> shift, on-resistance (R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> ), and dynamic R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> . A comprehensive study of TID effects are demonstrated in this article to verify different mechanisms and their interactions. Simulations using PHITs were also carried out to further confirm the damages in the epitaxial structure by the accumulated dose.

Comparison of Total Ionizing Dose Effects in 22-nm and 28-nm FD SOI Technologies

Total ionizing dose (TID) effects from Co-60 gamma ray and heavy ion irradiation were studied at the 22-nm FD SOI technology node and compared with the testing results from the 28-nm FD SOI technology. Ring oscillators (RO) designed with inverters, NAND2, and NOR2 gates were used to observe the output frequency drift and current draw. Experimental results show a noticeable increased device current draw and decreases in RO frequencies where NOR2 ROs have the most degradation. As well, the functionality of a 256 kb SRAM block and shift-register chains were evaluated during C0-60 irradiation. SRAM functionality deteriorated at 325 krad(Si) of the total dosage, while the FF chains remained functional up to 1 Mrad(Si). Overall, the 22-nm FD SOI results show better resilience to TID effects compared to the 28-nm FD SOI technology node.

Investigation of total ionizing dose effects in 4H–SiC power MOSFET under gamma ray radiation

In this work, the gamma ray radiation-induced total ionizing dose (TID) effects in SiC power MOSFETs are investigated. The transistor characteristics, such as transfer curve, output curve, drain-source ON-state resistance and terminal capacitance, are characterized to quantify the radiation tolerance. The threshold voltage is found to be sensitive to radiation and decreases with radiation dose increasing. An increased drive current and decreased drain-source ON-state resistance are resulted due to the decreased threshold voltage. The increased gate input capacitance exists after radiation. Verified in Sentaurus TCAD 2D simulation, the radiation-induced trap charge and interface states at SiO2/SiC interface are found to dominate the degradation of electrical behaviors in SiC power MOSFET.

The Influence of 10 MeV Proton Irradiation on Silicon Carbide Power Metal-Oxide-Semiconductor Field-Effect Transistor

The effects of 10 MeV proton irradiation on the threshold voltage and gate oxide reliability of SiC MOSFET are investigated. The negative shift of the threshold voltage was observed after irradiation, and the magnitude of the shift is exclusively related to the fluence and not the drain voltage. Moreover, proton irradiation leads up to the degeneration of oxide reliability. Experiment and simulation results indicate that the shift of the threshold voltage is caused by the total ionizing dose effect. Due to the superior blocking capabilities of the SiC MOSFET, the electric field of gate oxide is almost unaffected by the voltage applied to the drain, so the drift of threshold voltage is only related to particle fluence. The single event effect is responsible for the degradation of gate oxide reliability. The single event effect induces a transient high electric field in the gate oxide, which generates defects and affects the reliability of the gate oxide.

Localized Backside Etching Structure of SOI Substrates on Total Ionizing Dose Effect Hardening for RF Applications

In this work, the localized backside etching (LBE) structure is introduced as a strategy for total ionizing dose (TID) irradiation hardening. Immunity to TID-irradiation-induced radio frequency (RF) property degradation is observed for the first time in SOI substrates with the LBE structure. Identical co-planar waveguide transmission lines (CPW TLines), crosstalk characterization structures, and planar spiral inductors are designed and fabricated on different 8-in SOI wafers to characterize the RF properties of substrates. Electrical characterization in the frequency ranges from 100 MHz to 40 GHz reveals that the LBE structure is beneficial to suppressing the parasitic surface conduction (PSC) effect, which will lead to better RF properties of SOI substrate. It is shown that under <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">60</sup> Co <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -ray irradiation, RF losses are significantly increased in the case of conventional substrates. In contrast, LBE substrates are almost insensitive to TID irradiation due to suppression of PSC. A developed physical model is proposed to characterize the behavior of inductors under PSC and TID effects, and the improvement by LBE structure on RF TID tolerance is separated through model parameter extraction.

Study on Total Ionizing Dose Effect of Silicon Carbide Metal Oxide Semiconductor Field-Effect Transistors at High and Low Dose Rates

The total ionizing dose (TID) radiation effect of silicon carbide metal oxide semiconductor field-effect transistors (SiC MOSFETs) was investigated at different dose rates. The influence of irradiation dose rate on the transfer characteristic curves of the devices was investigated. And the threshold voltage, oxide trap charge, interface state, and peak transconductance et al. were further extracted based on the transfer curve. The results show that the degradation degree of irradiated devices varies at different dose rates due to the different factors. The degradation of the device at high dose rate is due to the radiation-induced oxide trap charge in the gate oxide layer, while the reason of the degradation at low dose rate is the radiation-induced oxide trap charges and interface state simultaneously, which have opposite effects on the devices, and the degradation degree depends on the competition between the two.

Total ionizing dose effects on aluminum oxide/zirconium-doped hafnium oxide stack ferroelectric tunneling junctions

Total ionizing dose effects on aluminum oxide/zirconium-doped hafnium oxide stack ferroelectric tunneling junctions

DC response, low-frequency noise, and TID-induced mechanisms in 16-nm FinFETs for high-energy physics experiments

Total-ionizing-dose (TID) mechanisms are evaluated in 16 nm Si bulk FinFETs at doses up to 1 Grad(SiO2) for applications in high-energy physics experiments. The TID effects are evaluated through DC and low-frequency noise measurements by varying irradiation bias conditions, transistor channel lengths, and fin/finger layouts. The TID response of nFinFETs irradiated under positive gate bias at ultrahigh doses shows a rebound of threshold voltage with significant increase in the 1/f noise amplitude. The degradation is related to the generation of border and interface traps at the upper corners of STI oxides and at the gate oxide/channel interfaces. In contrast, pFinFETs have the worst degradation due to positive charge trapping in STI oxides, which severely degrades the device transconductance and total drain current, while negligible effects are visible in the threshold voltage and 1/f noise. The TID sensitivity depends strongly on the transistor layout. Short-channel devices have the best TID tolerance thanks to the influence of halo implantations, while pFinFETs designed with low number of fins have the worst degradation because of high densities of positive charge in the surrounding thick STI oxides. As a guideline for IC design, short-channel transistors with more than 4-fins may be preferred in order to facilitate circuit qualification.

Total ionizing dose effect on 2-D array data transfer ICs designed and fabricated by 0.18 μm CMOS technology

Circuits for CMOS two-dimensional (2-D) array data transfer are indispensable for applications such as space and nuclear fields. Issues include being operated with higher speed, lower power, fewer size penalties, and radiation hardness. To meet these requirements, two kinds of CMOS 2-D array data transfer circuits, such as a shift register type and a memory access type, are proposed and fabricated by the standard 0.18 μm CMOS process technology. In both types, 16 μm pitch, 8 × 128 array data transfer operations were realized with a data rate of more than 1 Gb/s. Furthermore, we conducted 60Co γ-ray irradiation experiments on those circuits. The current consumption ratio of the shift register type to the memory access type ranges from 150 to 200% as the dosage increases. The result indicates that the memory access type has better radiation hardness at 1 Gb/s than that of the shift register type.

Total Ionizing Dose Effects on Read Noise of MLC 3-D NAND Memories

This article analyzes the total ionizing dose (TID) effects on noise characteristics of commercial multi-level-cell (MLC) 3-D NAND memory technology during the read operation. The chips were exposed to a Co-60 gamma-ray source for up to 100 krad(Si) of TID. We find that the number of noisy cells in the irradiated chip increases with TID. Bit-flip noise was more dominant for cells in an erased state during irradiation compared to programmed cells.

Total Ionizing Dose Effects on Long-Term Data Retention Characteristics of Commercial 3-D NAND Memories

This article evaluates the data retention characteristics of irradiated multilevel-cell (MLC) 3-D NAND flash memories. We irradiated the memory chips by a Co-60 gamma-ray source for up to 50 krad(Si) and then wrote a random data pattern on the irradiated chips to find their retention characteristics. The experimental results show that the data retention property of the irradiated chips is significantly degraded when compared to the un-irradiated ones. We evaluated two independent strategies to improve the data retention characteristics of the irradiated chips. The first method involves high-temperature annealing of the irradiated chips, while the second method suggests preprogramming the memory modules before deploying them into radiation-prone environments.

Comparison of Total Ionizing Dose Effects in SOI FinFETs Between Room and High Temperature

The synergetic effects of total ionization dose and high-temperature stress of SOI FinFETs are investigated under ON-state bias condition. The experiments and TCAD simulations are employed to analyze the influence of different trapped-charges in the gate and buried oxide on the threshold voltage and mobility variations on the ON-state current of the devices. Results show that the threshold voltage degradation worsens for n-SOI FinFETs but weakens for the p-SOI FinFETs. Also, the ON-state current of n-SOI FinFETs is significantly enhanced while the change of p-SOI FinFETs is weak under the synergetic effects. The threshold voltage degradation induced by synergetic effects for both n- and p-type SOI FinFETs can exceed the linear superposition of the two types of stresses, which may be related to the thermal release of trapped charges in the gate oxide. The enhanced degradation in the n-SOI FinFETs compared with the p-SOI FinFETs may result from the shallow energy level electron traps in HfO2. Besides, for both n- and p-type SOI FinFETs, the ON-state current variations under the synergetic effects depend on the competitive process of threshold voltage variation and the mobility fluctuation.

The influences of radiation effects on DC/RF performances of L g = 22 nm gate-all-around nanosheet field-effect transistor

In this paper, we carried out detailed technology computer aided design simulations to investigate the radiation effects, e.g. total ionizing dose (TID) and single-event effects (SEEs), on direct current (DC) and radio frequency (RF) characteristics of the gate-all-around (GAA) nanosheet field-effect transistor (FET). The simulation model used is composed of seven-layer stacked GAA nanosheet FET with L g = 22 nm, which was implemented in this study. The open current and the drain-induced barrier lowering of the device are ∼3 mA μm−1 and 47 mV V−1, respectively. The results indicate that the TID have little influence on the DC and RF characteristics when the transistor is working in an open state. During the SEEs simulation, we considered three incident directions for the high energy particle, including the lateral direction of the channels, the vertical direction of the channels and the top of the channels. The influence of the particle injecting along the lateral and vertical directions of the channels shows stronger relation with the distance from the incident point compared to the influence of the particle from the top. Besides, the general influence of the particle injecting along the lateral directions of the channels is higher than the other two directions. The total injected charge of the particle injecting along the lateral direction, along the vertical direction and from the top are 3 fC, 1.4 fC and 2.1 fC, respectively. As compared to the fin FET, the GAA nanosheet has superior RF performances and less sensitivity to TID effect. This work can provide a guideline for the GAA nanosheet devices in aerospace and avionic RF applications.

Influence mechanism and recognition algorithm of CMOS active pixel sensor radiation damage on star sensor star map recognition

In order to analyze the causes of star sensor performance degradation and attitude measurement accuracy reduction in space radiation environment, the total ionizing dose effects on complementary metal oxide semiconductor (CMOS) star sensor performance are studied. By using an established outfield star sensor test system, the Orion Nebula and the zenith direction of the sky are imaged. Through the experimental processes of star map data acquisition, star point extraction and star map matching, the influence mechanisms of complementary metal oxide semiconductor active pixel sensor (CMOS APS) noises on background gray mean value of star map and number of identified stars are analyzed. A recognition algorithm for finding stars annihilated by radiated noise is proposed. Through theoretical derivation, the quantitative relationships between CMOS APS dark current noise, dark signal non-uniformity noise and photon response non-uniformity noise and star centroid positioning error are established. The γ radiation results show that the image gray-mean of the whole star map increases, the number of identified stars decreases, and the star point centroid positioning accuracy decreases, which seriously affect star map recognition of star sensor. This research provides a theoretical basis for the radiation-resistant reinforcement design of high precision star sensors.

Total Ionizing Dose Effects of the Color Complementary Metal Oxide Semiconductor (CMOS) Image Sensor at Different Bias

The experiments of total ionizing dose radiation effects on color CMOS image sensors at different biases were presented. Two bias conditions operated during 60Co γ irradiation, biased and unbiased. In the data processing, the data of four channels were extracted according to the sequence of Bayer array respectively to study the difference between each channel. The full well capacity and dark signal non-uniformity versus the cumulative doses were investigated. After γ-ray irradiation, the full well capacity of the samples decreased along with dark signal non-uniformity increased. Meanwhile, the descending amplitude of full well capacity was different in each channel, but the variation of dark signal non-uniformity was almost consistent. Moreover, the degradations of full well capacity and dark signal non-uniformity were more seriously under-biased.

Three-dimensional simulation of total ionizing dose effect on SiGe heterojunction bipolor transistor

The damage mechanism of the total ionizing dose (TID) effect of SiGe heterojunction bipolor transistar (SiGe HBT) is explored by using three-dimensional simulation of semiconductor device (TCAD).In the simulation, the trapped charge defects are introduced into different locations of oxidationin SiGe HBT to simulate the TID effect. Then the degradation characteristics of the forward Gummel characteristic and the reverse Gummel characteristic of the device are analyzed, and the TID damage law of SiGe HBT is obtained. Finally, the simulation results are compared with the &lt;sup&gt;60&lt;/sup&gt;Co γ irradiation test results, showing that the trapped charges introduced by TID irradiation in SiGe HBT device mainly affect the Si/SiO&lt;sub&gt;2&lt;/sub&gt; interface near the p-n junction, resulting in the change in the depletion region of the p-n junction and the increase of carrier recombination. Eventually, the base current increases and the gain decreases. The trapped charges generated in the EB spacer oxide layer mainly affect the forward Gummel characteristics, and the trapped charges in the LOCOS isolation oxide layer are the main factor causing the reverse Gummel characteristics to degrade. The experimental results on &lt;sup&gt;60&lt;/sup&gt;Co γ irradiation under different biases are consistent with those from the total dose effect damage law of SiGe HBT obtained by numerical simulation analysis.

Radiation-hardened property of single-walled carbon nanotube film-based field-effect transistors under low-energy proton irradiation

Strong C–C bonds, nanoscale cross-section and low atomic number make single-walled carbon nanotubes (SWCNTs) a potential candidate material for integrated circuits (ICs) applied in outer space. However, very little work combines the simulation calculations with the electrical measurements of SWCNT field-effect transistors (FETs), which limits further understanding on the mechanisms of radiation effects. Here, SWCNT film-based FETs were fabricated to explore the total ionizing dose (TID) and displacement damage effect on the electrical performance under low-energy proton irradiation with different fluences up to 1 × 1015 p/cm2. Large negative shift of the threshold voltage and obvious decrease of the on-state current verified the TID effect caused in the oxide layer. The stability of the subthreshold swing and the off-state current reveals that the displacement damage caused in the CNT layer is not serious, which proves that the CNT film is radiation-hardened. Specially, according to the simulation, we found the displacement damage caused by protons is different in the source/drain contact area and channel area, leading to varying degrees of change for the contact resistance and sheet resistance. Having analyzed the simulation results and electrical measurements, we explained the low-energy proton irradiation mechanism of the CNT FETs, which is essential for the construction of radiation-hardened CNT film-based ICs for aircrafts.

Research on Total Ionizing Dose Effect and Reinforcement of SOI-TFET.

Since the oxide/source overlap structure can improve the tunneling probability and on-state current of tunneling field effect transistor (TFET) devices, and the silicon-on-insulator (SOI) structure has the effect of resisting the single event effect, SOI-TFET with the oxide/source overlap structure is a device with development potential. The total ionizing dose (TID) effect on SOI-TFET was studied by discussing the switching ratio, band–band tunneling rate, threshold voltage, sub-threshold swing and bipolar effect of the device under different doses of irradiation. At the same time, simulations prove that selecting the proper thickness of the buried oxide (BOX) layer can effectively reduce the influence of the TID effect. This provides a way of direction and method for research on the irradiation effects on the device in the future.

Total Ionizing Dose Effects on Nanosheet Gate-All-Around MOSFETs Built on Void Embedded Silicon on Insulator Substrate

The total ionizing dose response of nanosheet gate-all-around metal-oxide-semiconductor field effect transistor (NS GAA MOSFET) fabricated on novel void-embedded silicon on insulator (VESOI) substrate was investigated in this work. Strong radiation tolerance with as small as 46.6mV threshold voltage shift and non-discernable increase of off-state current were observed even at a dose of 7Mrad(Si) X-ray irradiation. Both the experiment and simulation results reveal that the radiation tolerance of the MOSFET device can be inherently attributed to the GAA channel. Our work undoubtedly demonstrates that the NS GAA device on VESOI substrate has great potential for radiation-harden applications under heavy radiation environment.