You can do this with the help of Web Methods by calling them with jQuery.
Step 1:- Write a stored procedure which will give you records according your needs.
Step 2:- Write ADO.Net Code to call the Stored Procedure.
Step 3:- Write a Web Method in your code behind file as static which will call DAL method to get results.
Step 4:- Send the results in JSON format from your web method.
Step 5:- Call this web method from jQuery when you type employee details.
Please visit links:-
Calling ASP.Net WebMethods using jQuery