This paper presents an overview and perspective on processing technologies required for continued scaling of leading edge and emerging semiconductor devices. We introduce the main drivers and trends affecting future semiconductor device scaling and provide examples of emerging devices and architectures that may be implemented within the next 10-20 yr. We summarize multiple active areas of research to explain how future thin film deposition, etch, and patterning technologies can enable 3D (vertical) power, performance, area, and cost scaling. Emerging and new process technologies will be required to enable improved contacts, scaled and future devices and interconnects, monolithic 3D integration, and new computing architectures. These process technologies are explained and discussed with a focus on opportunities for continued improvement and innovation.

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The challenges of reducing gate leakage current and dielectric breakdown beyond the 45 nm technology node have shifted engineers' attention from the traditional and proven dielectric SiO 2 to materials of higher dielectric constant also known as high-k materials such as hafnium oxide ͑HfO 2 ͒ and aluminum oxide ͑Al 2 O 3 ͒. These high-k materials are projected to replace silicon oxide ͑SiO 2 ͒. In order to address the complex process integration and reliability issues, it is important to investigate the mechanical properties of these dielectric materials in addition to their electrical properties. In this study, HfO 2 and Al 2 O 3 have been fabricated using atomic layer deposition ͑ALD͒ on ͑100͒ p-type Si wafers. Using nanoindentation and the continuous stiffness method, we report the elastomechanical properties of HfO 2 and Al 2 O 3 on Si. ALD HfO 2 thin films were measured to have a hardness of 9.5 Ϯ 2 GPa and a modulus of 220 Ϯ 40 GPa, whereas the ALD Al 2 O 3 thin films have a hardness of 10.5 Ϯ 2 GPa and a modulus of 220 Ϯ 40 GPa. The two materials are also distinguished by very different interface properties. HfO 2 forms a hafnium silicate interlayer, which influences its nanoindentation properties close to the interface with the Si substrate, while Al 2 O 3 does not exhibit any interlayer.For the past 40 years the microelectronics industry has relied on the scaling down of device size in order to improve the performance, functionality, and bit density of chips, as described by Moore's law. As microelectronics is transitioning into deep nanotechnology, the drawback of the increasing miniaturization of devices is the increase of gate leakage current and oxide breakdown. 1 To reduce the gate leakage current and breakdown field across the gate insulator, researchers are looking into high-k dielectric materials. High-k materials such as HfO 2 and Al 2 O 3 will increase the transistor drive current and the transistor switching speed. 2 HfO 2 is predicted to replace SiO 2 , SiO x N y , and Si 3 N 4 as the gate dielectric of complementary metal oxide semiconductor ͑CMOS͒ devices at the 45 nm technology node and beyond. HfO 2 and Al 2 O 3 have dielectric constants of approximately k = 25 and 8, respectively, 3 which compare favorably with k = 3.9 for SiO 2 . Various deposition techniques have been used to deposit high-k materials. Among these growth techniques are metallorganic chemical vapor deposition ͑MOCVD͒, 4-6 pulsed laser deposition ͑PLD͒, 7 and atomic layer deposition ͑ALD͒. 4-6,8 MOCVD and PLD require a high temperature during processing and film fabrication. 9 For example, a minimum temperature of 600°C is required to deposit HfO 2 with MOCVD, whereas HfO 2 crystallizes once the temperature reaches 600°C. 10 ALD is a chemical reactionbased deposition technique that requires only relatively low temperatures. ALD provides absolute film deposition uniformity ͑atomic layer by atomic layer͒, precise composition control, high conformality, and completely self-limiting surface reactions, which makes ALD the most...

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Crystalline materials with broken inversion symmetry can exhibit a spontaneous electric polarization, which originates from a microscopic electric dipole moment. Long-range polar or anti-polar order of such permanent dipoles gives rise to ferroelectricity or antiferroelectricity, respectively. However, the recently discovered antiferroelectrics of fluorite structure (HfO2 and ZrO2) are different: A non-polar phase transforms into a polar phase by spontaneous inversion symmetry breaking upon the application of an electric field. Here, we show that this structural transition in antiferroelectric ZrO2 gives rise to a negative capacitance, which is promising for overcoming the fundamental limits of energy efficiency in electronics. Our findings provide insight into the thermodynamically forbidden region of the antiferroelectric transition in ZrO2 and extend the concept of negative capacitance beyond ferroelectricity. This shows that negative capacitance is a more general phenomenon than previously thought and can be expected in a much broader range of materials exhibiting structural phase transitions.