| 摘要 |
A semiconductor structure having buried word line formed in a trench in a semiconductor substrate includes a gate oxide layer, a gate conductor, a gate cap layer, a blocking layer, and an isolation structure. The gate oxide layer is formed on the inner surface of the trench, the gate conductor is formed in the trench, and the gate cap layer is formed on the gate conductor. The blocking layer surrounds a bottom portion of the gate conductor, and the bottom portion of the gate conductor is isolated from the gate oxide layer by the blocking layer. The isolation structure surrounds a top portion of the gate conductor and in contact with the top end of the blocking layer. The top portion of the gate conductor is isolated from the gate oxide layer and the from the gate cap layer by the isolation structure. |
| 主权项 |
1. A semiconductor structure having buried word line, formed in a trench in a semiconductor substrate, comprising:
a gate oxide layer, formed on the inner surface of the trench; a gate conductor, formed in the trench; a gate cap layer, formed on the gate conductor, wherein the gate cap layer includes a first cap layer and a second cap layer, the second cap layer is disposed on the first cap layer, the first cap layer is made of TEOS oxide and the second cap layer and the first cap layer are made of different materials; a blocking layer, disposed surrounding a bottom portion of the gate conductor, wherein the bottom portion of the gate conductor is isolated from the gate oxide layer by the blocking layer; and an isolation structure, surrounding a top portion of the gate conductor and in contact with the top end of the blocking layer, wherein the top portion of the gate conductor is isolated from the gate oxide layer and the gate cap layer by the isolation structure. |
