I was able to create the instance after specifying fully qualified name of the assembly.
Thanks @Hans
Dictionary<string, TraceListener> dListeners = new Dictionary<string, TraceListener>();
string sType = "System.Diagnostics.ConsoleTraceListener, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089";
Type oType = Type.GetType(sType);
dListeners["Listener1"] = (TraceListener)Activator.CreateInstance(oType);