GaAs的ICP选择刻蚀研究

Selective etching of GaAs/AlGaAs by ICP

选择刻蚀在GaAs工艺中是非常重要的一步。由于湿法腐蚀存在钻蚀和选择性差,且精度难以控制，因此有必要进行干法刻蚀的研究。虽然采用反应离子刻蚀（RIE）、磁增强反应离子刻蚀（MERIE）可以进行选择刻蚀，但是这两种方法在挖槽时会对器件造成较大损伤，影响器件性能。感应耦合等离子刻蚀（ICP）是一种低损伤、高刻蚀速率高选择比的刻蚀方法,在GaAs器件的制造中有突出的优点。本工作进行了GaAs/AlGaAs的选择刻蚀研究，GaAs/AlGaAs的选择比达到840:1,取得较理想的刻蚀结果。

Selective etching is an important step in GaAs process. As the wet－ etching leads to undercut,poor selectivity and unrepeatable etching rate. It is necessary to research the dry etching. Although RIE and MERIE dry etching can be used for selective etching, they can cause serious damage, which affects the performance of devices and MMIC. ICP (inductive couple plasma) is a new method for low damage, high etching rate and high selective etching . In this paper, the selective etching of GaAs/AlGaAs is presented. The etching selectivity ratio of GaAs to AlGaAs is over 840:1 .