The　terahertz　spatial　light　modulator　(THz　SLM)　is　a　crucial　device　for　the　dynamic　modulation　of　terahertz　waves.　It　is　beneficial　in　the　fields　of　THz　imaging　and　photonic　computing.　For　example,　we　could　encode　and　perform　compressive　sensing　using　THz　SLMs.　Compared　with　THz　SLMs　working　in　the　reflective　mode,　the　transmission　mode　THz　SLMs　(T-THz　SLMs)　show　an　obvious　advantage　in　insertion　loss.　Due　to　the　ultra-low　insertion　loss,　several　T-SLMs　could　be　used　in　series,　greatly　facilitating　its　application　of　optical　computing.　In　this　study,　we　designed　an　electrically　driven　T-THz　SLM,　which　the　MEMS　approach　could　fabricate.　To　enhance　the　performance　of　the　T-THz　SLM,　the　T-THz　SLM　was　designed　to　be　prepared　for　freestanding　ultra-thin　silicon　nitride　windows.　Owing　to　the　merits　of　ultra-low　thermal　capacitance　and　high　transmission　of　the　devices,　a　high-speed,　low-power-consumption,　low-insertion-loss,　broadband　T-THz　SLM　would　be　realized.　©　2024　SPIE.