国产4H-SiC SI衬底MESFET外延生长及器件研制

Device Development and MESFET Epitaxy Growth on Domestic 4H-SiC SI Substrate

以国产衬底实现SiC加工工艺链为目标,采用国产4H-SiC半绝缘衬底材料外延得到4H-SiC MESFET结构材料。外延片XRD半宽43.2 arcs,方块电阻121点均匀性18.39%,随后制备出的具有直流特性的4H-SiC MESFET器件管芯,器件总栅宽250μm,饱和电流密度680 mA/mm,跨导约为20 mS/mm,在20 V下的栅漏截止漏电为10μA,2 mA下栅漏击穿电压为80 V。比例占总数的70%以上。初步实现从衬底到外延,进而实现器件的完整工艺链,为进一步的工艺循环打下良好基础。

In order to make the SiC process circle from substrate to device all by domestic materials, MESFET was grown on domestic SI dH-SiC substrate with vanadium doped. The XRD FWHM of the epilayer was 43.2 arcs. The uniformity of 121-dot sheet resistance mapping is 18.39% （standard deviation）. Then it was used in making MESFET devices. The gate-width is 250 μm. Idss is 680 mA/mm. The gm is about 20 mS/mm. The breakdown voltages between gate and drain are 20 V and 80 V at leak current 10 μA and 2 mA, respectively. The rate of final devices that passed DC test is more than 70%. The work is the beginning for making the process line of substrate, epitaxy and devices into succeed. It will be the start point for the next work.