Texture Induced Noise And Its Impact On System Performance

In rigid disk drive applications, mechanical performance is the primary factor in the design of the disk surface structure. The substrate of a thin film disk is often textured in order to reduce the stiction force between the head and disk. It was reported that the texturing process sacrifices magnetic performance for mechanical necessity [1]. The randomness of the disk surface structure due to substrate texture introduces an extra noise into the system. The texture noise was found to be density dependent and can be related to disk surface structure [2]. Direct correlation between the noise power and system error rate was observed [1]. However, how the disk surface structure affects the data storage and recovery processes remained to be understood. In this work, the effects of substrate texture on thin film disk noise and its impact on system performance are systematically investigated.