On Epitaxy of Ultrathin Ni[sub 1−x]Pt[sub x] Silicide Films on Si(001)

Abstract

Epitaxial Ni(Pt)Si 2-y (y<1) films readily grow upon thermal treatment of 2-nm thick Ni

Thermal Stability and Dopant Segregation for Schottky Diodes With Ultrathin Epitaxial $\hbox{NiSi}_{2 - y}$

“…It is worth noting that the temperature behavior in Fig. 1 is identical to that for the NiSi 2-y formation at different silicidation temperatures [2], [5]. For comparison, poly-Ni 1-x Pt x Si films of comparable thickness tend to agglomerate with a sharp resistance increase below 600 o C [2], [3].…”

“…Interaction of the 3-nm thick Ni film with Si(100) at 500 o C leads to epitaxial growth of NiSi 2-y , according to extensive XTEM, diffraction, pole-figure, resistance, and Raman analyses [2]- [5]. After B and As I/I, the resistance of the silicide films is rather high around 150 Ω/□ as shown in Fig.…”

“…For the Schottky diodes formed at 500 o C, the SBH extraction failed due to a large leakage current. The leakage could be due to some imperfections at the interface of the ultrathin epitaxial NiSi 2-y film formed at 500 o C [2], [5]. For the NiSi 2-y films formed at 750 o C with a much improved interfacial morphology in Fig.…”

“…For the NiSi 2-y films formed at 750 o C with a much improved interfacial morphology in Fig. 2(c) [2], [5],  bn =0.81 eV was obtained while it remained to be challenging to extract the low  bp due to large leakage. This  bn value is almost identical to that extracted for type-B NiSi 2 epitaxially grown on Si(111), i.e., 0.79 eV [22].…”

“…For these technology nodes, Ni-based silicide will most likely continue its dominance in the source/drain contact formation. Recent publications show that a NiSi 2-y film grows epitaxially on Si(100) if the initial thickness of Ni-Pt alloys is less than 4 nm and the Pt addition is restricted below 10% [2]- [5]. Polycrystalline Ni 1-x Pt x Si films will form for other thickness and/or composition combinations.…”