diff --git a/mesonbuild/compilers/fortran.py b/mesonbuild/compilers/fortran.py
index d09b4423a..a16f2b554 100644
--- a/mesonbuild/compilers/fortran.py
+++ b/mesonbuild/compilers/fortran.py
@@ -181,12 +181,13 @@ class FortranCompiler(Compiler):
 
     def module_name_to_filename(self, module_name: str) -> str:
         if '_' in module_name:  # submodule
+            s = module_name.lower()
             if self.id in ('gcc', 'intel'):
-                filename = module_name.lower() + '.smod'
+                filename = s.replace('_', '@') + '.smod'
             elif self.id in ('pgi', 'flang'):
-                filename = module_name.lower() + '.mod'
+                filename = s.replace('_', '-') + '.mod'
             else:
-                filename = module_name.lower() + '.mod'
+                filename = s + '.mod'
         else:  # module
             filename = module_name.lower() + '.mod'