Hi Prashanthi,
The name for that bond or agreement is "Non-Disclosure Agreement." You may search in CITEHR or Google, and you will get different formats. The Non-Disclosure Agreement is a legal contract between two parties (employer and employee) restricting the employee from joining a competitor company after resignation for a stipulated period, not poaching current employees, and not sharing company client/project secrets with a competitor company.
If you want to prohibit your ex-employee from working for your competitors, it means all employers in a similar business to yours will be your competitors. So, if you prohibit this in the form of a bond/agreement, they will work for their survival. What is your view on this?