Total dose responses and reliability issues of 65 nm NMOSFETs

In this paper,total dose responses and reliability issues of MOSFETs fabricated by 65 nm CMOS technology were examined. ＂Radiation-induced narrow channel effect＂ is observed in a narrow channel device.Similar to total dose responses of NMOSFETs,narrow channel NMOSFEs have larger hot-carrier-induced degradation than wide channel devices.Step Time-Dependent Dielectric Breakdown（TDDB） stresses are applied,and narrow channel devices have higher breakdown voltage than wide channel devices,which agree with ＂weakest link＂ theory of TDDB.Experimental results show that linear current,transconductance,saturated drain current and subthreshold swing are superposed degenerated by total dose irradiation and reliability issues,which may result in different lifetime from that considering total dose irradiation reliability issues separately.

Total Ionizing Dose Response of Different Length Devices in 0.13μm Partially Depleted Silicon-on-Insulator Technology

An anomalous total dose effect that the long length device is more susceptible to total ionizing dose than the short one is observed with the 0.13？μm partially depleted silicon-on-insulator technology. The measured results and 3D technology computer aided design simulations demonstrate that the devices with different channel lengths may exhibit an enhanced reverse short channel effect after radiation. It is ascribed to that the halo or pocket implants introduced in processes results in non-uniform channel doping profiles along the device length and trapped charges in the shallow trench isolation regions.

Influence of Total Ionizing Dose Irradiation on Low-Frequency Noise Responses in Partially Depleted SOI nMOSFETs

Total ionizing dose effect induced low frequency degradations in 130nm partially depleted silicon-on-insulator （SOI） technology are studied by ^60Co γ -ray irradiation. The experimental results show that the flicker noise at the front gate is not affected by the radiation since the radiation induced trapped charge in the thin gate oxide can be ignored. However, both the Lorenz spectrum noise, which is related to the linear kink effect （LKE） at the front gate, and the flicker noise at the back gate are sensitive to radiation. The radiation induced trapped charge in shallow trench isolation and the buried oxide can deplete the nearby body region and can activate the traps which reside in the depletion region. These traps act as a GR center and accelerate the consumption of the accumulated holes in the floating body. It results in the attenuation of the LKE and the increase of the Lorenz spectrum noise. Simultaneously, the radiation induced trapped charge in the buried oxide can directly lead to an enhanced flicker noise at the back gate. The trapped charge density in the buried oxide is extracted to increase from 2.21×10^18 eV^-1 cm^-3 to 3.59×10^18？eV^-1 cm^-3 after irradiation.