Heavy-ion-induced soft breakdown of thin gate oxides

Abstract

Abstract-Heavy-ion-induced soft and hard breakdown are investigated in thin gate oxides as a function of linear energy transfer, fluence, and voltage applied during irradiation. It is found that postirradiation oxide conduction is well described by the Suñé quantum point contact model.

Observation of latent reliability degradation in ultrathin oxides after heavy-ion irradiation

“…[1][2][3][4][5][6][7][8][9][10][11] RILC has been observed for heavy ions, x-rays, and electrons with relatively low linear energy transfers ͑LETs͒ between 10 and 40 MeV-cm 2 -mg Ϫ1 . RILC has been modeled as inelastic trap-assisted-tunneling due to neutral oxide defects and was found to be very similar to stress-induced-leakage current ͑SILC͒ observed after constant voltage stress.…”

Growth of heavy ion-induced nanodots at the SiO2–Si interface: Correlation with ultrathin gate oxide reliability

“…The track diameter can easily range up to 10 nm. In the case of soft break- downs, some results indicate that the heavy ion irradiation substantially reduces the intrinsic oxide lifetime [27]. The leakage path is currently considered to be a permanent conductive region.…”

“…It is well known that thin oxides are susceptible to a variety of radiation effects such as Radiation Soft Breakdown [23], Radiation Induced Leakage Current [24] and Single Event Gate Rupture [25,26]. But despite those recent works, the effects of radiation on ultrathin oxides is not fully understood [27]. Concerning SEGR or even Single Event Burnout, it is well assumed that these processes are field-assisted degradation modes during the heavy ion path.…”

“…Recent studies have pointed out that radiation induced soft breakdown may even occur for 4 nm thin oxides [28]. Numbers of results concerning the oxide reliability are still under investigation [27] and recent relevant models have been developed such as the ÔQuantum PointÕ Contact Model [29].…”

Single Event Gate Rupture in 130-nm CMOS Transistor Arrays Subjected to X-Ray Irradiation

“…After the event, a conductive path through the gate dielectric of (at least) one of the transistors in the array is present. During irradiation we monitored the gate current at the stress voltage and periodically (every second) we sampled the gate current at low voltage 250 mV in order to detect soft breakdown events [21]. The sense voltage does not stress at all the gate oxide, but it is useful to Fig.…”