1.3μm应变补偿多量子阱SLD台面制作工艺的研究

Study on Mesa Etch Process for 1.3 μm SC-MQW SLD

台面制作工艺对1.3μm应变补偿多量子阱SLD的器件性能有重要的影响。根据外延结构,分析比较了两种台面制作的方法,即选择性湿法腐蚀法和ICP刻蚀+湿法腐蚀法。InGaAs层ICP刻蚀避免了湿法腐蚀中的侧向钻蚀现象,Cl2含量为30%时速率可达到420nm/min;湿法腐蚀可有效减小ICP刻蚀引入的晶格损伤。SEM图像表明,ICP刻蚀+湿法腐蚀的台面制作方法,得到的腐蚀台面陡直,波导宽度与设计值更接近,优于选择性湿法腐蚀方法,更适合SLD台面制作。

Etch process plays an important role on the characteristics of 1.3μm SC-MQW superluminescent diode. Basing on its epitaxy structure, two kinds of mesa etch process, selective wet etching and ICP etching ＋ wet etching, were compared in order to find the best process. ICP etching process on the InGaAs layer can avoid the side eroding phenomena. The ICP etching rate can reach to 420 nm/min when Cl2 content is about 30%. Wet etching process can reduce the lattice damage introduced by the ICP etching. SEM image shows that the side wall of the mesa is steeper and the width of the waveguide is closer to the design when ICP etching and wet etching are combined. So this method is superior to the one with selective wet etching only.