Background: Little research exists on students' misconceptions about semiconductors, why they form, and what role educational resources like simulations play in misconception formation. Research on misconceptions can help enhance student learning about semiconductors. Purpose (Hypothesis): This project sought to identify students' misconceptions about three semiconductor phenomena -- diffusion, drift, and excitation -- and to determine if prior knowledge, knowledge acquired from watching animated simulations, or both were related to students' misconceptions. We hypothesized that students would hold misconceptions about those phenomena and that students' prior knowledge and knowledge acquired from watching animated simulations would be associated with their misconceptions. Design/Method: Forty-one engineering students completed an instrument that asked questions about three semiconductor phenomena after the students had observed the animated simulations. Responses were analyzed and coded using two frameworks: misconception and knowledge use. Results: Misconceptions were prevalent for all three phenomena. Misconceptions were associated with use of incorrect prior knowledge, a combination of correct or incorrect prior knowledge, and the knowledge acquired from watching the animated simulations alone or in combination with correct and incorrect prior knowledge. Misconceptions indicated a lack of understanding of chemistry and physics concepts. Conclusions: Findings indicate that students hold many misconceptions about semiconductor phenomena. These misconceptions were common among our participants. The knowledge acquired from the animated simulations alone or in combination with prior knowledge could reinforce or contribute to misconception formation. Our findings can guide instructors to use or create better simulations to aid student learning.