| abstract |
Embodiments of the invention are provided which include compositions of buffered oxide etch (BOE) solutions and methods that use the BOE solutions during a process to selectively remove a native oxide layer from a substrate surface containing thermal oxide layers. The BOE solutions generally contain HF and alkanolamine compounds. The viscosity of the BOE solution may be adjusted by varying a concentration ratio of at least two alkanolamine compounds. In one example, a BOE solution is provided which includes, by weight, a first alkanolamine concentration within a range from about 0.5% to about 10%, a second alkanolamine concentration within a range from about 0.5% to about 10%, a HF concentration within a range from about 0.5% to about 10%, a water concentration within a range from about 80% to about 98%, a pH value within a range from about 3.5 to about 5, and a viscosity within a range from about 10 cP to about 30 cP. |