I would write like this

Dear Dr. xx

Thank you for taking the time to talk to me about xxx position. I appreciate your time and consideration in interviewing me for this position. I am convinced that I would be a perfect candidate for this position.

I have not received the call from HR of your company. I am looking forward to hearing from you for the further on-site interview.

In addition, I would be more than happy to give a 15-30 minutes presentation in on-site interview.

Thank you again.

Sincerely,

xxx