Pressing Backspace Button deletes IFrame-IE 11

$(document).on("keydown", function (e) {
    if (e.which === 8 && !$(e.target).is("input, textarea")) {
        e.preventDefault();
    }
});

<script type = "text/javascript" >
function disableBackButton()
{
window.history.forward();
}
setTimeout("disableBackButton()", 0);
</script>

protected void btnLogOut_Click(object sender, EventArgs e)
{
       Session.Abandon();
       respose.redirect("Login.aspx");
}