Currently, we are reaching capacity limits in conventional Si-based memory devices, due to restrictions on further miniaturization. The concept of antiferromagnetic spin electronics (spintronics) has gained much traction to overcome this challenge. It has become clear that AFMs are actually vastly advantageous to realize memory devices, being far more robust than FM-based devices, with high packing density, and insensitivity to external fields. Unfortunately, to date, only a few materials have emerged as candidates. Thus, in our research, we have searched for the new non-collinear AFM Mn3X (X = Ga, Sn) materials and have fabricated them in thin film form. In order to access its fundamental magnetic property, we will use a magnetic neutron scattering technique to observe its noncollinear magnetic configuration.