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The effect of cluster carbon implantation and recrystallization on properties of phosphorus doped Si (Si:P) epitaxial films was investigated. Recrystallization techniques based on solid phase epitaxy with rapid thermal annealing (RTA), spike RTA (sRTA), and millisecond laser annealing were employed. It was found that strained carbon doped Si:P (Si:CP) layers with high [C]sub can be achieved by using low temperature sRTA/RTA due to the suppression of carbon–phosphorus coclustering in Si. Additional laser annealing can activate the remaining “nonactive” P atoms in the Si:CP layer recrystallized at low temperatures such as 900 °C sRTA and 800 °C 5 s RTA. This approach of combining a low temperature recrystallization anneal with an additional high temperature laser anneal was found to be useful for creating Si:CP layers with good crystallinity, low resistivity, and less phosphorus diffusion. Finally, a tensile strain was confirmed to be induced into the transistor channel by implementing the recrystallization technique on three dimensional fin-shaped field effect transistor device structures. A high recrystallization temperature of 1025 °C sRTA was found to be required for achieving complete recrystallization and suppressing introduction of defects/stacking faults in a Si:CP source/drain region. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate the impact of radical oxygen plasma on nitrided and annealed atomic layer deposited (ALD) SiO2 as a thick gate oxide (1.65-3 V) with a high-k/ metal gate transistor. Time-dependent-dielectric-breakdown voltage, secondary ion mass spectroscopy (SIMS), and x-ray photoelectron spectroscopy (XPS) studies were conducted, and the results are discussed for nitrided and annealed ALD SiO2 with and without radical oxygen plasma exposure. Atomistic material simulations were performed to understand the reactions between oxygen radicals and silicon oxynitride (SiON). Our key findings from SIMS and XPS show that radical oxygen plasma exposure led to a 34% nitrogen loss from the thick SiON gate oxide and damaged the gate oxide, resulting in a 1V reduction in the dielectric breakdown voltage. Atomistic material simulation results also show that atomic oxygen can react with Si-(ON)- Si to form Si-O-Si bonds and mobilize NO into the interstitial space. Similarly, when O atoms and O2 molecules are placed near N clusters, spontaneous diffusion of N2 into the interstitial space occurs. Diffusion barrier calculations further indicate a barrier energy of less than 0.5 eV in SiO2 and SiON, which can lead to the out-diffusion of NO and N2 from SiO2 and SiON. These compositional changes may result in increased leakage and a degraded breakdown voltage. The increased gate leakage and degraded breakdown voltage is attributed to the compositional changes in SiON. [ABSTRACT FROM AUTHOR]