Dear Pooja,
Gopi is right in mentioning that you can get employee treated in the ESI Hospital / Dispensary once he has become the ESI member.
Now comes the second part i.e. Sickness Benefit which is given as under:
"55. Sickness benefit
(1) Subject to the provisions of the Act and the regulations, a person shall be qualified to claim sickness benefit for sickness occurring during any benefit period if the contribution in respect of him were payable for not less than 36[seventy-eight days in] of the corresponding contribution period and shall be entitled to receive such benefit at the daily standard benefit rate for the period of his sickness:
PROVIDED that he shall not be entitled to the benefits for the first two days of sickness in the case of a spell of sickness following, at an interval of not more than fifteen days, the spell of sickness for which sickness benefits were last paid:
PROVIDED FURTHER that sickness benefits shall not be paid to any person for more than ninety-one days in any two consecutive benefit periods.
(2) The daily rate of sickness benefits in respect of a person during any benefit period shall be the "standard benefit rate" specified in rule 54 corresponding to the average daily wages of that person during the corresponding contribution period."
This is that benefit which is paid by ESI for the period during which the employee remains absent form his duties.
Hope now matter is cleared.
You can further ask for clarifiaction, if any.