Growth Study of p-Type 4H-SiC with Using Aluminum and Nitrogen Co-Doping by 2-Zone Heating Sublimation Method

Abstract

p-type SiC crystals doped with aluminum and nitrogen were grown by the sublimation method. We found that Al and N co-doping is effective for stabilized growth of p-type 4H-SiC polytype. We studied the relationship of polytype of grown crystals and the condition of Al and N feeding during the crystal growth. p-type 4H-SiC withp~1 x 1018cm-3are stably-obtained with this method.

Growth of Low Resistivity p-Type 4H-SiC Crystals by Sublimation with Using Aluminum and Nitrogen Co-Doping

“…It shows that the crystals with the Al concentration ~ 1× 10 20 cm -3 tend to be 6H-SiC when its N concentration is small compared to the Al concentration. This tendency corresponds to our previous report which show the 4H polytype could be stabilize with the appropriate Al-N co-doping condition [1]. 1) taken after the molten KOH etching treatment at 500°C.…”

“…It is also shown in Fig. 2(b), in the less N concentration growth condition, the 6H-SiC polytype is stably grown after the 6H polytype formation on n-type 4H-SiC layer which indicate the higher Al doping growth condition is suitable for 6H-SiC growth [1,2] .…”

“…However, there are few studies from sublimation grown p-type bulk crystals [2,7] and it was not clear whether such a low resistive 4H-SiC can be grown or not. In our previous study, we reported that 4H-SiC bulk crystals can be grown by sublimation by using Al-N co-doping method [1]. We further optimized the p-type SiC growth method and obtained low resistive 4H-SiC crystals with < 100 mΩcm which is the lowest resistivity for the p-type 4H-SiC grown by sublimation.…”

“…

Low resistivity p-type SiC bulk crystals were grown by the sublimation method with using aluminum and nitrogen co-doping. In the sublimation growth of 4H-SiC, to obtain lowresistive p-type crystals is not easy because of the instability of 4H-SiC polytype with highly Aldoping [1,2]. We have grown < 90 mΩcm p-type 4H-SiC bulk crystals with the co-doping condition.

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Low V F 4H-SiC N-i-P diodes using newly developed low-resistivity p-type substrates

“…Recently, heavily doped p-type 4H-SiC crystals grown by the PVT method, using a two-zone heating furnace with two radiofrequency (RF) coils, have been reported. [14][15][16] In this setup, aluminum carbide (Al 4 C 3 ) is used for p-type dopants, and the amounts of Al doping density and Al partial pressure are adjusted by the heating temperatures of Al 4 C 3 .…”