Dopant influence on polysilicon capacitor oxide failure
In this work, we investigate polysilicon capacitor oxide defectivity as a function of dopant contamination in a 0.5 /spl mu/m mixed signal process. Experiments show that shallow n and p type dopant implants, used to mimic a cross contamination problem discovered in a PECVD cluster tool, can significantly degrade oxide integrity. Various possible mechanisms of the increased defectivity are discussed.
On the electrical conduction in the interpolysilicon dielectric layers
To reduce the low-field electrical conductivity of interpolysilicon dielectrics used in electrically erasable programmable read-only (EEPROM) memories devices, the roughness of the poly-SiO/sub 2/ interface until now has been decreased in two ways: (1) by increasing the temperature of oxidation and doping of polysilicon combined with low-pressure chemical vapor deposition (LPCVD) of silicon (undoped or in-situ doped) in the amorphous phase, or (2) by the use of LPCVD high-temperature oxide (HTO) deposited over polycrystalline silicon. The advantages of both methods are combined, and electrical conduction results for an interpoly structure based on LPCVD smooth surface polysilicon and LPCVD HTO SiO/sub 2/ are presented. The data are interpreted in terms of the Fowler-Nordheim mechanism.<<ETX>>
Boron Diffusion Through Pure Silicon Oxide and Oxynitride Used for Metal‐Oxide‐Semiconductor Devices
We studied boron diffusion in thin silicon oxides including pure SiO 2 and oxynitride that are used for metal-oxide-semiconductor transistors. We measured the boron penetration using secondary ion mass spectrometry. By comparing simulated and experimental results, we found that the boron diffusivity in pure SiO 2 , D PO , is 3.96 × 10 -2 exp (-3.65eVLkT) cm 2 /s, and that in oxynitride containing 4% nitrogen, D NO , is 3.42 × 10 -2 exp (-3.75 eV.kT) cm 2 /s