Dear Arpita,
You do not require any MOU between employer and employee. Once you issue the the Appointment Order under the provisions of Factory Act or Shops and Commercial Establishments Act, a valid and legally tenable relationship is established.
To get the work done from employee, you can issue the letter on company letter head. Obtain the signature of the employee on each page for "ready to abide with the instructions given".
Investopedia defines MOU as "A legal document outlining the terms and details of an agreement between parties, including each parties requirements and responsibilities".
Here two parties are not separate business entities. MOU signed on the authorised bond paper is valid between the two parties.
Secondly, probably your company is small at this stage. Today you may get the MOU on 1-2 employees. But then as the strength of the employees will you be able to sign this bond papers? Will it not be time consuming as well as costly? Please ponder over these points also.
Thanks,
Dinesh V Divekar