【摘要】 用AB腐蚀液对SI GaAs晶片进行AB微缺陷显示 (AB微缺陷密度AB EPD :10 3～ 10 4 cm- 2 量级 ) ,用KOH腐蚀液显示位错 (位错密度EPD :10 4cm- 2 量级 ) ,发现衬底上的位错对器件跨导没有明显的影响 ,而用AB腐蚀液显示的AB微缺陷对器件性能及均匀性有明确的影响 :低AB EPD的片子跨导大 ;高AB EPD的片子跨导小。AB EPD有一临界值 ,当AB EPD高于此值时 ,跨导陡然下降。另外 ,还利用扫描光致发光光谱 (PLmapping)对衬底进行了测量 ,得出了与上述结果相符的结果。更多还原

【Abstract】 We found dislocations density （EPD） of the substrate revealed by KOH solution has no definite effect on g_m of the MESFET, while the density of the precipitate-like microscopic defects （AB-EPD） revealed by AB solution has. The AB-EPD ranged from 10³ to 10⁴ cm^-2, while the average EPD is of the order of 10⁴ cm^-2. It is found that g_m is large in the case of low AB-EPD wafer, while it is small in the case of high AB-EPD wafer. There is a critical value for AB-EPD, once AB-EPD is higher than the critical value, g_m dropps dramatically. The quality of substrates were also studied by PL mapping whose result agrees with the above results.更多还原