In　this　paper,　we　investigated　the　application　of　n-type　hydrogenated　microcrystalline　silicon　oxide　(n-mu　c-SiOx:H)　as　the　front　surface　field　(FSF)　to　improve　the　short-circuit　current　density　(J(SC))　of　silicon　heterojunction　(SHJ)　solar　cells.　The　advantage　of　employing　n-mu　c-SiOx:H　layer　is　due　to　its　low　optical　absorption　coefficient　and　tunable　refractive　index.　However,　the　SHJ　solar　cell　performance　was　otherwise　limited　by　the　amorphous　oxygen　alloyed　silicon-based　films　which　probably　deteriorate　the　incubation　stage　of　the　n-mu　c-SiOx:H　layer.　To　reduce　amorphous/microcrystalline　mixture　phase　during　the　growth,　we　implemented　high　phosphorus-doped　seed　layer　deposited　prior　to　n-mu　c-SiOx:H　layer　with　refractive　indices　in　the　range　of　2.7　to　2.9.　Finally,　optimization　of　the　n-mu　c-SiOx:H　layer　led　to　a　conversion　efficiency　of　23.9%,　with　J(SC)　of　39.1mA/cm(2),　open　circuit　voltage　(V-OC)　of　740mV,　and　fill　factor　(FF)　of　82.6%.