How to define schema of API key in securitySchemes for OpenAPI?

I want to define the format/schema for the API key as a UUID in the securitySchemes section of my OpenAPI spec. Below are my two attempts, neither of which pass validation with error Schema validation: Property 'format' / 'schema' is not allowed.

Can this be done and what would the right syntax be?

components:
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      schema:
        type: string
        format: uuid
      in: header
      name: authToken

components:
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      format: uuid
      in: header
      name: authToken

you need to define the securityScheme component and you can additionally define the same header name, in this case, authorization as a request parameter at the operation level.

openapi: 3.0.4
info:
  title: Example API
  version: 1.0.0
  description: An example API to demonstrate OpenAPI specification with security schemes.
paths:
  'things/':
    get:
      summary: List things
      security:
        - apiKey: []
      parameters:
        - $ref: '#/components/parameters/header_authorization'
components:
  securitySchemes:
    apiKey:
      type: apiKey
      name: authorization
      in: header
  parameters:
    header_authorization:
      name: authorization
      in: header
      required: true
      schema:
        type: string
        format: uuid