Johan Swerts

0.5 nm EOT low leakage ALD SrTiO 3 on TiN MIM capacitors for DRAM applications

We demonstrate for the first time record low Leakage-EOT (3.5 times 10-7 A/cm2 at 1V, EOT=0.49 nm) MIM capacitors fabricated using a low temperature (250degC) ALD SrTiO3 (STO) deposition process on ALD TiN bottom electrode. While most previous work on STO used deposition techniques not compatible with high aspect ratio DRAM applications, recent work on ALD STO showed promise on noble-like metal electrodes (Ru, Pt) [1,2]. In this work, a low temperature ALD process with alternative precursor set and carefully optimized deposition and processing conditions enables the use of low-cost, manufacturable-friendly TiN electrode MIMcaps for future DRAM nodes. Composition (Sr-rich) and process optimization allowed minimization of interfacial EOT penalties and leakage reduction by decreasing the density of leakier STO grains.

Tailoring Fe∕Ag superparamagnetic composites by multilayer deposition

Fe∕Ag granular multilayers were examined by magnetization and Mossbauer spectroscopy measurements. Very-thin (0.2 nm) discontinuous Fe layers show superparamagnetic properties that can be tailored by the thickness of both the magnetic and the spacer layers. Novel heterostructures, superparamagnetic and ferromagnetic layers stacked in different sequences, were prepared and the specific contribution of the ferromagnetic layers to the low-field magnetic susceptibility was identified.

Evolution of perpendicular magnetized tunnel junctions upon annealing

We study the evolution of perpendicularly magnetized tunnel junctions under 300 to 400

New Mechanisms for Ozone-Based ALD Growth of High-k Dielectrics via Nitrogen-Oxygen Species

^{circ}

In-plane vector magnetometry on rectangular Co dots using polarized neutron reflectivity

C annealing. The hysteresis loops do not evolve much during annealing and they are not informative of the underlying structural evolutions. These evolutions are better revealed by the frequencies of the ferromagnetic resonance eigenmodes of the tunnel junction. Their modeling provides the exchange couplings and the layers anisotropies within the stack which can serve as a diagnosis of the tunnel junction state after each annealing step. The anisotropies of the two CoFeB-based parts and the two Co/Pt-based parts of the tunnel junction decay at different rates during annealing. The ferromagnet exchange coupling through the texture-breaking Ta layer fails above 375

Atomic Layer Deposition: An Enabling Technology for Microelectronic Device Manufacturing

^{circ}

Nitrogen Profile and Dielectric Cap Layer (Al2O3, Dy2O3, La2O3) Engineering on Hf-Silicate

C. The Ru spacer meant to promote a synthetic antiferromagnet behavior is also insufficiently robust to annealing. Based on these evolutions we propose optimization routes for the next generation tunnel junctions.

Atomic layer deposition of GdHfOx thin films

Ozone (O3) is a commonly used oxidant in ALD of various high-k metal oxides. Commercially available ozone delivery systems commonly rely on the dielectric barrier discharge and often utilize nitrogen in the feed gas to provide consistent ozone generation. Through a complex series of plasma reactions, various NxOy species can also form within the corona from O2 in the presence of N2. These species, while present in various concentrations in the generator effluent, are unregulated by the delivery system which measures and actively controls the O3 concentration only.

Remote plasma activated nitridation

We have measured the off-specular polarized neutron reflectivity of a periodic array of rectangular polycrystalline magnetic Co dots, which were prepared by a combination of electron beam lithography and molecular beam deposition. The dots have strong shape anisotropy, imposed by a length-to-width ratio of 4:1. The intensity of the first-order off-specular satellite reflection was monitored as function of the magnetic field parallel to the rows of dots, allowing us to analyze the magnetization reversal process using the four spin-polarized scattering cross sections.

Invited) Plasma Enhanced Atomic Layer Deposited Ruthenium for MIMCAP Applications

Atomic layer deposition (ALD) recently emerged as an enabling technology for microelectronic device fabrication. This technique provides the unique capability to deposit ultra thin films with the thickness control, uniformity, step coverage, and electrical/mechanical properties required to support device manufacturing at the 45 nm node and beyond. This paper will review the fundamentals of ALD processing and describe the equipment used. Applications of ALD in the fabrication of advanced gate stacks, on-chip capacitors, and thin film magnetic heads are presented.