A governing board may grant sabbatical leave to a faculty member at the state institution of higher education under its jurisdiction for the purpose of permitting him or her to engage in graduate study, research or other activities calculated to improve teaching ability. A governing board may grant a request for sabbatical leave only in accordance with the uniform rule it has promulgated and adopted. A governing board may not adopt a rule which provides for granting sabbatical leave to a faculty member who has served fewer than six years at the institution where presently employed, nor which provides for leave for more than one half the contract period at full pay or for a full contract period at half pay. A faculty member receiving a sabbatical leave is required to return and serve the institution granting the leave for at least one year or to repay to the institution the compensation received during leave. A faculty member returning from leave shall be reinstated at the academic rank held immediately prior to taking sabbatical leave unless he or she is promoted to a higher rank and is entitled to the salary and any salary increases appropriate to his or her rank and years of experience. The compensation for a faculty member on sabbatical leave is paid by the institution where employed from its regular personal services appropriations.