*2.2. Research on TMT Heterogeneity and Innovation*

Scholars have conducted extensive research on the impact of TMT heterogeneity on innovation. Researchers advocating a positive view believe that TMT heterogeneity is more likely to stimulate and amplify team members' creativity and innovation, which ultimately promotes the success of enterprise innovation [29]. Beckman (2006) [30] found that teams with a strong heterogeneity of work experience showed more exploratory and innovative behaviors because they have more external contacts and unique ideas. Henneke and Lüthje (2007) [31] pointed out that the composition of interdisciplinary entrepreneurial teams affects the quality of the enterprise's strategic planning process, thus indirectly promoting product innovation. Ni et al. (2016) [32] studied the impact of the balance of team heterogeneity on team creativity. They found that the balance of team knowledge heterogeneity can positively affect team creativity.

Researchers advocating a negative view believe that TMT heterogeneity is not necessarily more conducive to innovation than homogeneity. Amason et al. (2006) [33] found that in highly innovative enterprises, due to the increasing demand for face-to-face communication, the performance of homogeneous teams that could conduct open and collaborative communication was better than that of heterogeneous teams, a finding later supported by Elsbach and Kramer (2003) [34]. Chattopadhyay (1999) [35] argued that differences between team members significantly reduced mutual trust. This was not conducive to the information exchange and integration of the whole team and had a negative impact on innovation. Knight (1999) [36] found that the TMT education heterogeneity could increase the differences among members, trigger internal conflicts, and thus reduce the efficiency of enterprise decision making. The internal conflict caused by TMT heterogeneity also weakened the enterprise's innovation ability [37].

In summary, the existing research demonstrated the impact of TMT heterogeneity on innovation capability and innovation performance from different perspectives, but they have not yet reached a consensus or conclusion. In addition, there is a lack of research on the relationship between TMT experience heterogeneity and innovation quality. According to the patent statistics report of the World Intellectual Property Organization (WIPO) in recent years, the ratio of the effective amount to the applied amount of Chinese invention patents is low, the patent life is short, and a large number of invention patents become invalid before the protection period, which indicates that the patent quality is not high. Based on this, this paper will study the impact and mechanism of TMT experience heterogeneity on enterprise innovation quality to reveal the mechanism "black box" and theoretical boundary of this causal chain.

#### **3. Theory and Hypotheses**
