Electrical characteristics of thin boron carbonitride films on Ge(100) and Si(100)

Abstract

Metal insulator semiconductor structures were fabricated from n-Si(100) and n-Ge(100) wafers passivated with thin (4.5–5 nm) films of N-rich BCxNy (0.09≤x≤0.15, 0.38≤y≤0.52) and with atomic layer deposition HfO2 (10 nm) as the gate dielectric. C-V and I-V characteristics of devices with BCxNy films grown at 275–400 °C by chemical vapor deposition showed that lower deposition temperatures resulted in improved electrical characteristics, including decreased hysteresis, lower VFB shift, lower leakage current, and less C-V stretch out. The electrical improvement is attributed to decreased bulk and interfacial defects in lower temperature deposited BCxNy films, which also had a higher optical bandgap [Eg=3.55 eV at 275 °C on Ge(100)], lower subbandgap absorption, lower index of refraction [n(633 nm)=1.84 at 275 °C on Ge(100)], reduced O uptake during ambient exposure, and increased percentage of B. Even for the lowest growth temperature studied (275 °C), BCxNy-passivated Ge(100) devices had considerable hysteresis (1.05 V), and electrical characteristics worsened after a postmetallization anneal. BCxNy-passivated Si(100) devices outperformed similar Ge(100) devices likely due to the higher interface state densities at the BCxNy–Ge(100) interface associated with the higher relative inertness of Ge(100) to thermal nitridation. C-rich BC0.61N0.08 films were also investigated but large amounts of hysteresis and fixed negative charge motivated the abandonment of these films.

Effect of nitrogen pressure on structure and optical properties of pulsed laser deposited BCN thin films

“…Both theoretical calculations and experimental studies show that BCN compounds exhibit excellent mechanical, optical and electrical properties [1][2][3]. In particular, the possibility to control the band gap (E g ) by atomic composition and structure makes them good candidates for the application in electronic and photonic devices [3][4][5]. Various deposition techniques have been developed for depositing BCN thin films, including chemical vapor deposition (CVD) [3,6], radio frequency magnetron sputtering [7], ion beam assisted deposition [1,8], cathodic arc plasma deposition [9], DC magnetron sputtering [10] and pulsed laser deposition (PLD) [2].…”

Optical Studies of Reactively Co-Sputtered BCN Thin Films

“…Both theoretical calculations and experimental studies show that BCN compounds exhibit excellent mechanical, optical and electrical properties [1], [2]. The possibility to control the band gap (EG) by atomic composition and structure makes them good candidates for the application in electronic and photonic devices [3], [4]. In this work we deposited BCN thin films on quartz substrates by B 4 C and BN targets using RF and DC powers respectively at different N 2 /Ar gas flow ratios.…”

Nondestructive and Nonpreparative Chemical Nanometrology of Internal Material Interfaces at Tunable High Information Depths

“…Layered systems of conducting, semiconducting, and isolating nanosized films play a steadily increasing role in the effort to downscale electronic devices. Metals are used as conducting materials, whereas boron carbonitride (B x C y N z , referred to in this paper as BCN for simplicity) is in discussion as a semiconducting partner . Furthermore, h-BCN and c-BCN have outstanding mechanical, optical, and chemical properties .…”

“…Metals are used as conducting materials, whereas boron carbonitride (B x C y N z , referred to in this paper as BCN for simplicity) is in discussion as a semiconducting partner. 10 Furthermore, h-BCN and c-BCN have outstanding mechanical, optical, and chemical properties. 11 A detailed description of the synthesis and characterization of carbonitrides is provided elsewhere.…”