javascript - Pass an image through AJAX

Basically I want to pass a image file with ajax on submitting a form and retrieve the image and send it by email as an attachment file:

Here's the form :

    

        

            Company
            

                
            
        

        

            * Message
            

                
            
        
        

            Logo
            

            


                
                    
                        Parcourir 
                    
                
                
            
            
        
    


    

        
        
        
    
    

I can't seem to find what's the error in my code ! Here's the AJAX call :

jQuery(document).on("click", "#submit", function(e) {
      e.preventDefault();
      var fileInput = document.getElementById('image_input_field');
      var file = fileInput.files[0];
      var formData = new FormData();
      formData.append('file', file);
      // console.log(file);

      var societe = $("input#societe").val();

      var message = $("textarea#message").val();
      jQuery.ajax({
        url: "ajax.php",
        type: "post",
        data: {
           'file': file,
           'module' : 'ajax_data_form',
           'societe': societe,
           'message': message
        },

        cache: false,

        success: function(reponse) {
          if(reponse) {
            alert(reponse);
            // console.log(reponse);
            // jQuery('#devis').trigger("reset");
          } else {
            alert('Erreur');
          }

        }
      });
     });

And here's the ajax.php:

if( isset($_POST['module']) && $_POST['module'] == "ajax_data_form" )
{

     var_dump($_FILES);
}