Areal density of hard dick drive soon faces limit due to various challenges of TMR materials for further reduction of size. With given geometry of current-perpendicularplane, alternative candidate for read sensor technology to overcome the drawbacks of TMR and CPP GMR with transition metal is the CPP GMR utilizing Heusler alloy (HA). This all metallic sensor stack with low resistance resolves possible issue of noise anchoring TMR technology. And the half metallic nature of HA boosts the signal output beyond the CPP GMR with transition metals. In order to be accommodated in the sensor stack in the order of 30nm and lower, it is highly critical to prepare ordered phase of HA with given thermal processing allowed in sensor stack fabrication. Furthermore, proper metrology is required to obtain the phase information from very thin HA. In the talk, NMR as a proper metrology to provide phase information is suggested among various analytical techniques.