请教：html中点击一个按钮后无法跳转到php

按钮代码如下

 <button id="singup" class="btn" onclick="signup();">sign up</button>
 <button id="signin" class="btn" onclick="signin();">sign in</button>

点击事件

 <script type="text/javascript">
            function signup() {
                $.ajax({
                    url: 'verifyNew.php', 
                    method: 'POST',
                    success: function(data) {
                        if(data.success == 1) { 
                            alert(data.msg);
                        }
                    }
                });
            }

php

 <?php
echo "Welcome"
?>