An　improved　peninsula-island　structured　pressure　sensor　was　presented　with　the　novel　dry-wet　combination　etching　process.　There　were　four　pairs　of　segmented　mass　blocks　attaching　on　the　back　of　the　diaphragm.　Each　segmented　mass　block　was　composed　of　a　peninsula　structure　and　an　island　structure　with　anisotropic-etching-induced　sidewalls.　The　improved　structure　not　only　inherited　the　stress　concentration　feature　of　low　strain　energy　dissipation　but　also　improved　the　comprehensive　ability　of　the　sensor　chip,　including　low　fabrication　cost,　high　etching　uniformity,　good　temperature　performance　and　low　residual　stress　in　the　diaphragm.　Also,　the　fabrication　method　combining　DRIE　(Deep　Reactive　Ion　Etching)　and　anisotropic　wet　etching　was　verified　by　the　simulation　based　on　the　Sentaurus　2013.　The　fabrication　error　caused　by　anisotropic　wet　etching　was　analyzed.　Compared　with　the　flat　film　of　the　same　size,　the　proposed　structure　can　increase　the　sensitivity　by　225%,　reduce　the　nonlinearity　by　80.3%,　and　increase　resonance　frequency　by　11%.　In　addition,　the　sensor　structure　can　also　be　applied　to　pressure　sensors　with　different　working　range,　which　will　be　helpful　to　design　the　pressure　sensors　with　high　efficiency　and　accuracy.　©　2020　IEEE.