hiqpdf, how to save file to server instead of attachment?

Question

I am trying to save a PDF file to a server path rather than downloading it as an attachment, which I have made with the "hiqpdf" tool. :

 protected void btnPrint_Click(object sender, EventArgs e)
    {
        // create the HTML to PDF converter
        HtmlToPdf htmlToPdfConverter = new HtmlToPdf();

        // set browser width
        htmlToPdfConverter.BrowserWidth = int.Parse("805");

        // set browser height if specified, otherwise use the default
        //if (textBoxBrowserHeight.Text.Length > 0)
        //    htmlToPdfConverter.BrowserHeight = int.Parse(textBoxBrowserHeight.Text);

        // set HTML Load timeout
        htmlToPdfConverter.HtmlLoadedTimeout = int.Parse("180");

        // set PDF page size and orientation
        htmlToPdfConverter.Document.PageSize = PdfPageSize.A4;
        htmlToPdfConverter.Document.PageOrientation = PdfPageOrientation.Portrait;

        // set PDF page margins
        htmlToPdfConverter.Document.Margins = new PdfMargins(0);

        // set a wait time before starting the conversion
        htmlToPdfConverter.WaitBeforeConvert = int.Parse("5");

        // convert HTML to PDF
        byte[] pdfBuffer = null;

        //if (radioButtonConvertUrl.Checked)
        //{
        // convert URL to a PDF memory buffer
        string url = System.Configuration.ConfigurationManager.AppSettings["SiteURL"] + "PrintFullApplicantProfile.aspx?MaidID=" + Request.QueryString["aid"].ToString();

        pdfBuffer = htmlToPdfConverter.ConvertUrlToMemory(url);            

        // inform the browser about the binary data format
        HttpContext.Current.Response.AddHeader("Content-Type", "application/pdf");

        // let the browser know how to open the PDF document, attachment or inline, and the file name
        //HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("{0}; filename=HtmlToPdf.pdf; size={1}",
        //    checkBoxOpenInline.Checked ? "inline" : "attachment", pdfBuffer.Length.ToString()));
        HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("{0}; filename=Applicant-" + Request.QueryString["aid"].ToString() + ".pdf; size={1}", "attachment", pdfBuffer.Length.ToString()));
        // write the PDF buffer to HTTP response
        HttpContext.Current.Response.BinaryWrite(pdfBuffer);

        // call End() method of HTTP response to stop ASP.NET page processing
        HttpContext.Current.Response.End();
    }

Any suggestion to save the file to the server path? Thanks in advance.