High-temperature　operating　characteristics　and　polarization　stability　are　important　for　VCSEL　as　an　atomic　clock　light　source.　In　this　study,　the　polarization-stable　single-mode　795　nm　VCSEL　with　anisotropic　aperture　was　successful　fabricated　by　controlled　the　asymmetric　airflow　distribution　and　the　different　oxidation　rates　of　the　crystal　direction.　The　oxidation　of　different　crystal　direction　of　asymmetric　oxidation　aperture　with　time　is　summarized..　The　surface　electric　fields　of　the　traditional　circular　oxidation　aperture　VCSEL(C-VCSEL)　and　diamond　shape　oxidation　aperture　VCSEL(D-VCSEL)　with　different　aperture　sizes　are　investigated　by　simulation,　and　then　the　cause　of　the　anisotropy　of　D-VCSEL　is　explored.　The　special　anisotropic　oxidation　aperture　of　the　device　makes　it　have　stable　polarized　characteristics.　The　demonstrated　D-VCSEL　with　dimensions　of　3.6　μm　×　4.8　μm,　achieving　an　orthogonal　polarization　suppression　ratio　(OPSR)　exceeding　30　dB　while　maintaining　low　threshold　and　high　single-mode　output　even　at　temperatures　up　to　80　°C.　©　2024　SPIE.