<!DOCTYPE html>
<html>
<body>
<p>Click the button to create a Month field.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
var x = document.createElement("INPUT");
x.setAttribute("type", "month");
x.setAttribute("value", "2014-01");
document.body.appendChild(x);
}
</script>
</body>
</html>