浮動保護環耐壓的穩定方法

專利類型

發明

專利國別 (專利申請國家)

中華民國

專利申請案號

111117125

專利證號

I 795286

專利獲證名稱

浮動保護環耐壓的穩定方法

專利所屬機關 (申請機關)

國立陽明交通大學

獲證日期

2023/03/01

技術說明

一種浮動保護環耐壓的穩定方法，適於具有一半導體基底層之高功率元件，該高功率元件之終端係形成有至少一浮動保護環，所述的穩定方法包含可先於此高功率元件之上表面依序形成有襯墊氧化層與屏蔽層，以曝露出該至少一浮動保護環，之後，進行一離子佈植步驟，並在去除襯墊氧化層與屏蔽層後成長場氧化層，使該場氧化層下方形成有一缺陷層，本發明係可藉由所形成之缺陷層，使場氧化層與半導體基底層之間介面的電位固定在一特定電位，使其不受場氧化層中電荷或是上方金屬層電位的影響，由此有效地穩定浮動保護環的崩潰電壓。 A method for stabilizing breakdown voltages of floating guard ring, which is applicable to a high power device, is provided. The high power device has a semiconductor substrate layer, and at least one floating guard ring is formed at its termination. The disclosed method includes sequentially providing a pad oxide layer and a barrier layer on an upper surface of the high power device to expose the floating guard ring, and then performing an ion implantation step. After removing the pad oxide layer and the barrier layer, grow a field oxide layer, such that a defect layer is formed underneath. By employing the formed defect layer, the present invention achieves to control an interface voltage level between the field oxide layer and the semiconductor substrate layer fixed at a certain voltage value, without being affected by charges in the field oxide layer or metal crossed over it, thereby stabilizing breakdown voltages of the floating guard ring.