use ComCoreServiceImpl as Impl;

    class Load {
        public static function service(String $class, array $params = array()){
            try {
                $ucfirstclass = ucfirst($class);
                if (interface_exists('\Com\Core\Service\' . $ucfirstclass)) {
                    $ref = "Impl\".$ucfirstclass;
                    return new $ref();
                } else {
                    throw new Exception("Service with name $class not found");
                }
            } catch (Throwable $ex) {
                echo $ex->getMessage();
            }
        }
    }

$userService = Load::service("user");

Class 'ImplUser' not found