InP-based nano grating and manufacturing method thereof

The invention provides an InP-based nano grating and a manufacturing method thereof. The manufacturing method comprises the steps of growing SiNx film on an InP-based wafer; sequentially spin coatingan anti-reflective coating and a photoresist layer, and forming a grating pattern on the photoresist layer by adopting a phase mask exposing and developing method; by means of a secondary exposing anddeveloping method, removing photoresist on the edge of the InP-based wafer, and wiping off the anti-reflective coating on the edge of the InP-based wafer; etching the anti-reflective coating to transfer the grating pattern on the photoresist layer onto the anti-reflective coating; etching the SiNx film to transfer the grating pattern on the anti-reflective coating onto the SiNx film; removing thephotoresist layer and the anti-reflective coating; etching the InP-based wafer to transfer the grating pattern on the SiNx film onto the InP-based wafer; removing the SiNx film and the residual anti-reflective coating on the S