Abstract
High-κ dielectrics are insulating materials with higher permittivity than silicon dioxide. These materials have already found application in microelectronics, mainly as gate insulators or passivating layers for silicon (Si) technology. However, since the last decade, the post-Si era began with the pervasive introduction of wide band gap (WBG) semiconductors, such as silicon carbide (SiC) and gallium nitride (GaN), which opened new perspectives for high-κ materials in these emerging technologies. In this context, aluminium and hafnium oxides (i.e., Al2O3, HfO2) and some rare earth oxides (e.g., CeO2, Gd2O3, Sc2O3) are promising high-κ binary oxides that can find application as gate dielectric layers in the next generation of high-power and high-frequency transistors based on SiC and GaN. This review paper gives a general overview of high-permittivity binary oxides thin films for post-Si electronic devices. In particular, focus is placed on high-κ binary oxides grown by atomic layer deposition on WBG semiconductors (silicon carbide and gallium nitride), as either amorphous or crystalline films. The impacts of deposition modes and pre- or postdeposition treatments are both discussed. Moreover, the dielectric behaviour of these films is also presented, and some examples of high-κ binary oxides applied to SiC and GaN transistors are reported. The potential advantages and the current limitations of these technologies are highlighted.
Highlights
Today, it is widely recognized that microelectronic devices have improved the quality of our daily lives, strongly contributing to the development of human civilization
As already mentioned in the introduction, most powered electronic devices based on silicon have used silicon dioxide (SiO2) as a gate dielectric
High-permittivity binary oxides for silicon carbide (SiC) and gallium nitride (GaN) electronic devices have attracted significant interest in the last decade because of the potential benefit they can bring in the device performances
Summary
It is widely recognized that microelectronic devices have improved the quality of our daily lives, strongly contributing to the development of human civilization. In other fields, such as electronic systems for power transmission or distribution (power converters, base stations, wireless connections, etc.) and optoelectronics (light emitting diodes—LEDs, lasers), the achievement of the ultimate silicon performances opened the route for the post-Si era In this context, wide band gap (WBG) semiconductors emerged as the most suitable materials for this technological revolution, especially in high-power and high-frequency electronics [4,5,6,7]. Their wide band gaps result in higher breakdown voltage and operation temperature with respect to Si, so both are excellent candidates to replace Si in the generation of high-power and high-frequency electronics Because of their different physical and electronic properties in terms of carrier mobility and thermal conductivity [8,9], SiC and GaN will cover different market segments in the post-Si technologies [10]. A great part of the results presented are related to high-κ oxides grown by ALD techniques
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call