本論文使用新型氮化鎵鋁材料系統蝕刻停止層(Etch-stop layer)結構，成功開發兩階段乾蝕刻製程來控制深蝕刻(>1μm)，對於單縱模操作的氮化鎵垂直共振腔面射型雷射(Vertical Cavity Surface Emitting Lasers，VCSEL)需要幾微米的垂直共振腔，因此可應用於精準控制氮化鎵VCSEL之共振腔腔長。
我們使用感應耦合電漿反應式離子蝕刻機(Inductively-Coupled Plasma Reactive Ion Etching，ICP-RIE)來進行乾蝕刻，以及配合適當的反應氣體、電漿功率，讓氮化鋁磊晶層與氟離子電漿產生化學反應而形成氟化鋁蝕刻停止層薄膜(Aluminum Fluoride，AlF3)，此蝕刻停止層可以使蝕刻率減緩至零來達到阻擋蝕刻的效果，藉此來控制蝕刻深度，而後再使用濕蝕刻的高選擇比特性來移除蝕刻停止層，一方面可以獲得較好的表面均勻性；另一方面則可以移除掉乾蝕刻時的物理轟擊所造成之表面損傷。

In this paper, we adopt new etch stop process for precisely controlling the cavity lengths of GaN-based vertical-cavity-surface-emitting lasers, successfully developing two-stage of the dry etching process which is used to control deep etching(more than 1μm). Fabrication of a vertical-cavity surface-emitting laser(VCSEL) array requires precise control in cavity length which is a couple of microns for single longitudinal mode operation, the new etch stop process can be applied to precisely control the cavity lengths of GaN-based vertical-cavity-surface-emitting lasers.
Inductively-coupled plasma reactive ion etching(ICP-RIE) is used for dry etching, with the appropriate reactant gas and plasma power to generate the chemical reaction between AlN and fluorine plasma. This forms AlF3 etch-stop layer which can dramatically decrease the etching rate to zero in order to form the etch-stop layer, so we can thereby control the depth of etching. After ICP-RIE, we adopt wet etching to remove the etch-stop layer by its high selective ratio. This process allows us to gain better root mean square roughness(RMS), in addition, we can also remove the damage on the surface which is caused by physical bombardment while conducting a dry etching process.

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