Electrical Characterization of PiN Diodes with p⁺ Layer Selectively Grown by VLS Transport

Abstract

This paper deals with electrical characterization of PiN diodes fabricated on an 8° off-axis 4H-SiC with a p++localized epitaxial area grown by Vapour-Liquid-Solid (VLS) transport. It provides for the first time evidence that a high quality p-n junction can be achieved by using this technique followed by a High Temperature Annealing (HTA) process.

Applications of Vapor-Liquid-Solid Selective Epitaxy of Highly p-Type Doped 4H-SiC: PiN Diodes with Peripheral Protection and Improvement of Specific Contact Resistance of Ohmic Contacts

“…6-a), which is the same on both on-axis and 8°-off epilayers and for both e-beam and sputtering techniques (not shown here). These observations agree with our previous work [9]. SBH and ideality factor vary in the range 1.3 < φ b < 2.8 eV and 1.4 < n < 2.9, respectively.…”

“…In our previous work, it was demonstrated that a rather good PN junction could be achieved by using a 1 µm deep p-type SEG-VLS layer into a n --type 4H-SiC epilayer [9]. As a step forward towards the use of such localized doping process in a functional device, we report here on the fabrication and characterization of PiN diodes using SEG-VLS process for the realization of the p+ doped emitter and guard ring peripheral protection.…”

Very low specific contact resistance measurements made on a highly p-type doped 4H-SiC layer selectively grown by vapor-liquid-solid transport

“…The VLS growth has been performed at 1100 C during 5 min with Ar as carrier gas and propane as carbon source. 13 Micro-Raman spectrometry, electron backscatter diffraction phase mapping and transmission electron microscopy observation (not shown here) did not display any evidence of 3 C polytype inclusion. The structure of the TLM pattern is reported in Fig.…”

“…11,12 Moreover, a high quality p þ (VLS)-n junction can be achieved by using this technique, which offers new prospects for the achievement of new power electronics devices, including deeply buried peripheral protection zones such as guard rings or Junction Barrier Schottky (JBS) structures. 13 This paper presents a study of ohmic contacts properties realized on p þ À type 4 H-SiC buried SEG-VLS layer.…”

Very High Sustainable Forward Current Densities on 4H-SiC p-n Junctions Formed by VLS Localized Epitaxy of Heavily Al-Doped p⁺⁺ Emitters

“…In order to compare our results with those previously presented in [6], breakdown voltage tests were performed under the same conditions, i.e. in air and at room temperature.…”