Method for improving influence of BPSG on contact resistance

The invention discloses a method for improving the influence of BPSG on contact resistance, and the method comprises the steps: carrying out the one-step rapid thermal annealing before the ion implantation of a contact hole or a groove in a wafer, forming a layer of oxidation film on the side wall of the groove or the contact hole in a BPSG layer, and carrying out the ion implantation and annealing of the contact hole. According to the method, the oxide film is formed as the barrier layer, impurity ions are sealed in the BPSG layer, and then the ion implantation and annealing process is carried out, so that the condition of impurity diffusion in the BPSG layer is avoided, and the reliability of the device is improved. 本发明公开了一种改善BPSG对接触电阻影响的方法，在晶圆上接触孔或沟槽的离子注入之前，先进行一步快速热退火，在BPSG层中的沟槽或者接触孔的侧壁上形成一层氧化膜，然后再进行接触孔离子注入及退火过程。通过形成一层氧化膜作为阻挡层，将杂质离子封闭在BPSG层内部，然后再进行离子注入及退火过程，这样避免了BPSG层内部杂质扩散的情况发生，提高器件可靠性。