Silicon　nanowires　(SiNWs)　were　fabricated　in　a　metal-assisted　chemical　etching　method　with　two　steps　including　dipping　silicon　wafers　in　AgNO3/HF　solutions　and　then　in　H2O2/HF　solutions.　Grazing　incidence　X-ray　diffraction　measurements　with　a　set　of　incidence　angles　were　carried　out　on　the　resulting　samples　to　detect　characteristics　of　silver　nanoparticles　in　the　etched　silicon.　Compared　with　the　uniform　size　of　silver　nanoparticles　on　the　surface,　the　silver　nanoparticles　in　etched　silicon　were　found　with　size　increasing　and　content　decreasing　corresponding　to　the　depths.　Based　on　the　silver　size　increasing　phenomenon,　a　detailed　supplementary　hypothesis　about　SiNWs　formation　was　proposed　about　silver　disintegration　and　redeposition　in　the　later　stage　of　silicon　etching.　For　2,　3,　4,　and　8　mM　AgNO3　solutions　used　to　study　their　effect　on　the　SiNWs,　it　was　found　that　a　higher　quantity　of　Ag+　concentration　such　as　8　mM　were　not　beneficial　for　producing　good　quality　SiNWs.　(C)　The　Author(s),　2020.　Published　by　Cambridge　University　Press　on　behalf　of　International　Centre　for　Diffraction　Data.