Patterning of silicon nitride for CMOS gate spacer technology. III. Investigation of synchronously pulsed CH3F/O2/He plasmas

Abstract

International audienc

Two-step cycling process alternating implantation and remote plasma etching for topographically selective etching: Application to Si3N4 spacer etching

“…9 Blanc et al showed that improved spacer process performance can be obtained by using synchronous pulsed plasma technology. 10 The switching on and off in a synchronous manner of both the source and bias powers at a low duty cycle allows us to decrease the average ion energy and the plasma chemical reactivity (more molecular than atomic), which ultimately reduce plasma induced damage. Although they showed that pulsed plasma process leads to minimized silicon recess and improved spacer profiles compared to CW plasma processes, the spacer process performance is still not satisfactory for advanced technology nodes.…”

Inductively coupled plasma etching of ultra-shallow Si3N4 nanostructures using SF6/C4F8 chemistry

“…It has been shown that the addition of C 4 F 8 in SF 6 plasma results in the reduction of available F species and increases the deposition rate of passivation film [13]. Even if inductively coupled plasma (ICP) technique is standardly used in industry for the etching of nanometric Si 3 N 4 spacers using fluorocarbon-based processes [4], etching processes of ultrashallow Si 3 N 4 nanostructures are really scarce in the literature.…”

“…In complementary metal-oxide-semiconductor (CMOS) technology, a precise Si 3 N 4 etching control and a high selectivity are required for applications such as gate spacers [4] or shallow trench isolation [5], where overetch needs to be damage-less for the underlying films or devices. In the fabrication of nanodevices, controllable slow etch rates are more and more demanded for the etching of thin films.…”

Dissociative ionization and electron beam induced deposition of tetrakis(dimethylamino)silane, a precursor for silicon nitride deposition

“…Silicon nitride (SiN x ) thin films are dielectric materials that play an important role in the semiconductor industry. By varying the silicon/nitrogen composition or deposition methods, such films can serve as passivation layers in device packaging, 1,2 insulators of interconnects in Back End of Line (BEOL), 3 gate spacers for high mobility channel transistor fabrication 4 and more. 5 Silicon oxynitrides (SiO x N y ) are also essential materials in the semiconductor industry 6 as a dielectric layer and for integrated optics and waveguides.…”