Leakage current through dielectric in transistors having the channel length up to 100 nm

The present work describes that by experimental means the dependence of the leakage current through the gate dielectric on the temperature in the metal-oxide-semiconductor transistor manufactured on “silicon-on-isolator” with 90 nm design standards were obtained. There was defined the contribution of such charge carries transfer mechanisms to the leakage current through the gate dielectric of 18 $\mathring{\mathrm{A}}$ thickness, as thermionic emission, field tunneling and Poole–Frenkel emission. Using numerical modeling there was developed transistor model calibrated by geometric, structural and electro-physical characteristics of the manufactured sample; distribution of the current density components, drift speed and field being orthogonal to the interface of transistor silicon-gate oxide were defined. There was also determined electron wavelength close to the transistor gate dielectric at maximum component of the drift speed. It is shown that the main mechanism for charge carries transfer through the gate dielectric is field tunneling. During the work effect of gamma radiation dose on the value of the tunnel leakage current through the gate dielectric was also investigated for defining Pool–Frenkel emission contribution on the value of the leakage current through the gate dielectric. The result of the work is determination that the contribution is insignificant as the radiation dose variation has weak effect on the tunnel leakage current. This is typical of high quality gate dielectrics.