| 초록 |
In this research, materials of 2-dimentional (2D) SnS2 and TiO2 were hybridized for highly improved reliability characteristic of resistive switching random access memory (RRAM) device. For comparison, 3 type of RRAM devices were fabricated and tested. The type 1, the reference device, has a W/TiO2/TiN structure, while the others (Type 2 and 3) have an additional SnS2 thin film as an active layer with different incoperation way. As shown in Fig. 1, Type 2 and 3 have a stack of W/SnS2/TiO2/TiN and W/(SnS2-TiO2, lamellar)/TiN, respectively. The total thinkness of each SnS2 and TiO2 thin film was identically controled in Type 2 and 3. All devices achieved fast switching speed (100 ns), CMOS compatibility (＜ 5 V), retention characterisitic (2 hours at 85℃) and multi-bit operation (3-bit: 1 HRS, 7LRS). With the developed RRAM devices, we demonstrated highly improved endurance characteristic ( ＞ 105 cycles), efficient multi-bit operation and uniform programming voltage distribution compared to the case of Type 1. To reveal the role of SnS2 material in the resistive switching, various analysis were performed, and it was found that the microscopic structure of hybridized material has a key role for desired performance. The detailed experimental processes, electrical measurement results, microsopic chemical and structual analysis will be introduced in presentation. |
