application letter for a PhD position

Dear Madam/ Sir
i am trying to compose a really impressive application letter for a PhD program
the previous that i have had used till now seems rather funny and i can hear laughter shots after my letter.
so i would be really obliged if could find a template or a typique format of such a letter.
regards

http://www.usingenglish.com/cgi-bin/...ump.cgi?ID=471

dear sir/mam

i want to get permission from my department to pursue Phd in electronics and communication engineering.
plz send a letter in impressive langusge so that i can get the permission

regards