get json from wikipedia services

Question

i am trying to get infobox from wikipedia services using jquery $.getJSON function.

This is my function:

function GetInfoboxWikipedia(sTerm){
    alert("Termo de pesquisa: " +sTerm);
    var url="http://en.wikipedia.org/w/api.php?action=parse&format=json&page=" + sTerm + "&redirects&prop=text&callback=?";
    var html = "";
    $.getJSON(url,function(data){
      wikiHTML = data.parse.text["*"];
      $wikiDOM = $("<document>"+wikiHTML+"</document>");
      alert("html: "+$wikiDOM.find('.infobox').html());
      html += $wikiDOM.find('.infobox').html();
    });
    return html;
}

i call it like this:

result_html += GetInfoboxWikipedia(searchTerm);

result_html is what i the html element i am appending to. ALthough the alerts in the function return correctly nothing appears. i think its because the call is asynchronous. How can i have the result_html += GetInfoboxWikipedia(searchTerm) returning the value when i enter in that part of the code?